---
type: Analog Component
title: "MAX17504 — 4.5V-60V, 3.5A, High-Efficiency, Synchronous Step-Down DC-DC Converter with Internal Compensation"
description: "4.5V-60V, 3.5A, High-Efficiency, Synchronous Step-Down DC-DC Converter with Internal Compensation"
resource: "https://www.analog.com/en/products/max17504.html"
tags: ["datasheet", "okf-r12-batch1", "maxim"]
generated: { by: "agentforge/aa0b0641", at: "2026-09-29T20:23:52Z" }
status: draft
sources:
  - id: "datasheet"
    resource: "https://www.analog.com/media/en/technical-documentation/data-sheets/max17504.pdf"
    title: "MAX17504 data sheet"
    author: "team:analog-devices"
tables:
  - file: "max17504/tables/table-00-p2-abs_max.csv"
    title: "Absolute Maximum Ratings"
    page: 2
  - file: "max17504/tables/table-01-p2-data.csv"
    title: "Package Information"
    page: 2
  - file: "max17504/tables/table-02-p2-spec.csv"
    title: "Electrical Characteristics"
    page: 2
  - file: "max17504/tables/table-03-p15-pin.csv"
    title: "Pin Description"
    page: 15
  - file: "max17504/tables/table-04-p18-data.csv"
    title: "Table 1. Switching Frequency vs. RT Resistor"
    page: 18
  - file: "max17504/tables/table-05-p20-data.csv"
    title: "Table 2. C6 Capacitor Value at Various Switching Frequencies"
    page: 20
  - file: "max17504/tables/table-06-p25-data.csv"
    title: "Ordering Information"
    page: 25
  - file: "max17504/tables/table-07-p26-data.csv"
    title: "Revision History"
    page: 26
figures:
  - file: "max17504/figures/max17504-f000.png"
    caption: ""
    type: "other"
    page: 1
  - file: "max17504/figures/max17504-f001.png"
    caption: "MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f002.png"
    caption: "MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f003.png"
    caption: "MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f004.png"
    caption: "MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f005.png"
    caption: "MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f006.png"
    caption: "MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f007.png"
    caption: "MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 5
  - file: "max17504/figures/max17504-f008.png"
    caption: "MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f009.png"
    caption: "MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f010.png"
    caption: "MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f011.png"
    caption: "MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f012.png"
    caption: "MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f013.png"
    caption: "MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f014.png"
    caption: "MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 6
  - file: "max17504/figures/max17504-f015.png"
    caption: "MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f016.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f017.png"
    caption: "MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f018.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f019.png"
    caption: "MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f020.png"
    caption: "MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f021.png"
    caption: "SWITCHING FREQUENCY vs. RT RESISTANCE"
    type: "characteristic_curve"
    page: 7
  - file: "max17504/figures/max17504-f022.png"
    caption: "MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f023.png"
    caption: "MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO, (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f024.png"
    caption: "MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f025.png"
    caption: "MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f026.png"
    caption: "MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f027.png"
    caption: "MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 8
  - file: "max17504/figures/max17504-f028.png"
    caption: "MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f029.png"
    caption: "MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f030.png"
    caption: "MAX17504S 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f031.png"
    caption: "MAX17504S 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f032.png"
    caption: "MAX17504 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f033.png"
    caption: "MAX17504 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PFM MODE, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f034.png"
    caption: "MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 9
  - file: "max17504/figures/max17504-f035.png"
    caption: "MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PWM MODE, NO LOAD, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f036.png"
    caption: "MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f037.png"
    caption: "MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mALOAD, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f038.png"
    caption: "MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 25mALOAD, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f039.png"
    caption: "MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (NO LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f040.png"
    caption: "MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mA LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f041.png"
    caption: "MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 150mA LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 10
  - file: "max17504/figures/max17504-f042.png"
    caption: "MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 1.7`5ATO 3.5A (PWM MODE, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f043.png"
    caption: "MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75ATO 3.5A (PWM MODE, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f044.png"
    caption: "MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f045.png"
    caption: "MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f046.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f047.png"
    caption: "MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 11
  - file: "max17504/figures/max17504-f048.png"
    caption: "MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-f049.png"
    caption: "MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-f050.png"
    caption: "MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-f051.png"
    caption: "MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-f052.png"
    caption: "MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f053.png"
    caption: "MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 4 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f054.png"
    caption: "MAX17504 5V OUTPUT OVERLOAD PROTECTION (FIGURE 3 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f055.png"
    caption: "MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f056.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f057.png"
    caption: "MAX17504S 5V OUTPUT OVERLOAD PROTECTION (FIGURE 5 CIRCUIT)"
    type: "scope_capture"
    page: 13
  - file: "max17504/figures/max17504-f058.png"
    caption: "MAX17504 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 700kHz (FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f059.png"
    caption: "MAX17504 5V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f060.png"
    caption: "MAX17504 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f061.png"
    caption: "MAX17504S 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 1.2MHz, (FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f062.png"
    caption: "MAX17504S 5V OUTPUT 4 BODE PLOT (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f063.png"
    caption: "MAX17504S 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)"
    type: "characteristic_curve"
    page: 14
  - file: "max17504/figures/max17504-f064.png"
    caption: ""
    type: "pinout"
    page: 15
  - file: "max17504/figures/max17504-f065.png"
    caption: ""
    type: "block_diagram"
    page: 16
  - file: "max17504/figures/max17504-f066.png"
    caption: "Figure 1. Setting the Input Undervoltage Lockout"
    type: "application_circuit"
    page: 19
  - file: "max17504/figures/max17504-f067.png"
    caption: "Figure 2. Setting the Output Voltage"
    type: "application_circuit"
    page: 20
  - file: "max17504/figures/max17504-f068.png"
    caption: ""
    type: "layout_drawing"
    page: 22
  - file: "max17504/figures/max17504-f069.png"
    caption: "Figure 3. MAX17504 Typical Application Circuit for 5V Output, 500kHz Switching Frequency"
    type: "application_circuit"
    page: 23
  - file: "max17504/figures/max17504-f070.png"
    caption: "Figure 4. MAX17504 Typical Application Circuit for 3.3V Output, 500kHz Switching Frequency"
    type: "application_circuit"
    page: 23
  - file: "max17504/figures/max17504-f071.png"
    caption: "Figure 5. MAX17504S Typical Operating Circuit for 5V Output, 1MHz Switching Frequency"
    type: "application_circuit"
    page: 24
  - file: "max17504/figures/max17504-f072.png"
    caption: "Figure 6. MAX17504S Typical Operating Circuit for 3.3V Output, 1MHz Switching Frequency"
    type: "application_circuit"
    page: 24
  - file: "max17504/figures/max17504-f073.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-f074.png"
    caption: "MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 6 CIRCUIT)"
    type: "scope_capture"
    page: 12
  - file: "max17504/figures/max17504-eq01.png"
    caption: "Equation as printed (p. 17)"
    type: equation
    page: 17
  - file: "max17504/figures/max17504-eq02.png"
    caption: "Equation as printed (p. 18)"
    type: equation
    page: 18
  - file: "max17504/figures/max17504-eq03.png"
    caption: "Equation as printed (p. 18)"
    type: equation
    page: 18
  - file: "max17504/figures/max17504-eq04.png"
    caption: "Equation as printed (p. 19)"
    type: equation
    page: 19
  - file: "max17504/figures/max17504-eq05.png"
    caption: "Equation as printed (p. 19)"
    type: equation
    page: 19
  - file: "max17504/figures/max17504-eq06.png"
    caption: "Equation as printed (p. 19)"
    type: equation
    page: 19
  - file: "max17504/figures/max17504-eq07.png"
    caption: "Equation as printed (p. 19)"
    type: equation
    page: 19
  - file: "max17504/figures/max17504-eq08.png"
    caption: "Equation as printed (p. 20)"
    type: equation
    page: 20
  - file: "max17504/figures/max17504-eq09.png"
    caption: "Equation as printed (p. 20)"
    type: equation
    page: 20
  - file: "max17504/figures/max17504-eq10.png"
    caption: "Equation as printed (p. 20)"
    type: equation
    page: 20
  - file: "max17504/figures/max17504-eq11.png"
    caption: "Equation as printed (p. 20)"
    type: equation
    page: 20
  - file: "max17504/figures/max17504-eq12.png"
    caption: "Equation as printed (p. 20)"
    type: equation
    page: 20
  - file: "max17504/figures/max17504-eq13.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
  - file: "max17504/figures/max17504-eq14.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
  - file: "max17504/figures/max17504-eq15.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
  - file: "max17504/figures/max17504-eq16.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
  - file: "max17504/figures/max17504-eq17.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
  - file: "max17504/figures/max17504-eq18.png"
    caption: "Equation as printed (p. 21)"
    type: equation
    page: 21
agentforge:
  part_number: "MAX17504"
  collection: "okf-r12-batch1"
---

# MAX17504 — 4.5V-60V, 3.5A, High-Efficiency, Synchronous Step-Down DC-DC Converter with Internal Compensation

*Datasheet: [MAX17504 data sheet (PDF)](https://www.analog.com/media/en/technical-documentation/data-sheets/max17504.pdf)*

### General Description

The MAX17504/MAX17504S high-efficiency, highvoltage, synchronously rectified step-down converter with dual  integrated  MOSFETs operates over a 4.5V to 60V input. It delivers up to 3.5A and 0.9V to 90% V IN  output voltage. Built-in compensation across the output voltage range eliminates the need for external components. The feedback (FB) regulation accuracy over -40°C to +125°C is  ±1.1%. The device is available in a compact (5mm x 5mm) TQFN lead (Pb)-free package with an exposed pad. Simulation models are available.

The device features a peak-current-mode control architecture  with  a  MODE  feature  that  can  be  used  to operate  the  device  in  pulse-width  modulation  (PWM), pulse-frequency modulation  (PFM),  or discontinuous mode (DCM) control schemes. PWM operation provides constant  frequency  operation  at  all  loads,  and  is  useful in  applications  sensitive  to  switching  frequency.  PFM operation disables negative inductor current and additionally skips pulses at light loads for high efficiency. DCM  features  constant  frequency  operation  down  to lighter  loads  than  PFM  mode,  by  not  skipping  pulses, but only disabling negative inductor current at light loads. DCM  operation  offers  efficiency  performance  that  lies between PWM and PFM modes. The MAX17504S offers a lower minimum on-time that allows for higher switching frequencies and a smaller solution size.

A programmable soft-start feature allows users to reduce input  inrush  current.  The  device  also  incorporates  an output  enable/undervoltage  lockout  pin  (EN/UVLO)  that allows the user to turn on the part at the desired inputvoltage  level.  An  open-drain RESET pin  provides  a delayed power-good signal to the sys­ tem upon achieving successful regulation of the output voltage.

### Applications

- Industrial Power Supplies
- Distributed Supply Regulation
- Base Station Power Supplies
- Wall Transformer Regulation
- High-Voltage Single-Board Systems
- General-Purpose Point-of-Load

### Benefits and Features

- Eliminates External Components and Reduces Total Cost
- No Schottky-Synchronous Operation for High Efficiency and Reduced Cost
- Internal compensation for Stable Operation at Any Output Voltage
- All Ceramic Capacitor Solution: Ultra-Compact Layout with as Few as Eight External Components
- Reduce Number of DC-DC Regulators to Stock
- Wide 4.5V to 60V Input Voltage Range
- 0.9V to 90% V IN  Output Voltage
- Delivers Up to 3.5A Over Temperature
- 100kHz to 2.2MHz Adjustable Frequency with External Synchronization
- MAX17504S Allows Higher Frequency Of Operation
- Available in a 20-Pin, 5mm x 5mm TQFN Package
- Reduce Power Dissipation
- Peak Efficiency > 90%
- PFM and DCM Modes for High Light-Load Efficiency
- Shutdown Current = 2.8 F A (typ)
- Operate Reliably
- Hiccup-Mode Current Limit and Autoretry Startup
- Built-In Output Voltage Monitoring-(Open-Drain RESET Pin)
- Resistor Programmable EN/UVLO Threshold
- Adjustable Soft-Start and Pre-Biased Power-Up
- High Industrial -40°C to +125°C Ambient Operating Temperature Range/-40°C to +150°C Junction Temperature Range

Ordering Information appears at end of data sheet.

### Absolute Maximum Ratings (Note 1)

**Absolute Maximum Ratings** ([table-00-p2-abs_max.csv](max17504/tables/table-00-p2-abs_max.csv), p. 2)

| PARAMETER | RATING |
|---|---|
| V_IN to PGND | -0.3V to +65V |
| EN/UVLO to SGND | -0.3V to +65V |
| LX to PGND | -0.3V to (V_IN + 0.3V) |
| BST to PGND | -0.3V to +70V |
| BST to LX | -0.3V to +6.5V |
| BST to V_CC | -0.3V to +65V |
| FB, CF, R̅E̅S̅E̅T̅, SS, MODE, SYNC, RT to SGND | -0.3V to +6.5V |
| V_CC to SGND | -0.3V to +6.5V |
| SGND to PGND | -0.3V to +0.3V |
| LX Total RMS Current | ±5.6A |
| Output Short-Circuit Duration | Continuous |
| Continuous Power Dissipation (T_A = +70°C) (multilayer board) TQFN (derate 33.3mW/°C above T_A = +70°C) | 2666.7mW |
| Junction Temperature | +150°C |
| Storage Temperature Range | -65°C to +160°C |
| Lead Temperature (soldering, 10s) | +300°C |
| Soldering Temperature (reflow) | +260°C |

Stresses beyond those listed under 'Absolute Maximum Ratings' may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

### Package Information

**Package Information** ([table-01-p2-data.csv](max17504/tables/table-01-p2-data.csv), p. 2)

| PACKAGE TYPE: 20 TQFN |  |
|---|---|
| Package Code | T2055+4 |
| Outline Number | 21-0140 |
| Land Pattern Number | 90-0009 |
| **THERMAL RESISTANCE, FOUR-LAYER BOARD** |  |
| Junction to Ambient (θ_JA) | 30°C/W |
| Junction to Case (θ_JC) | 2°C/W |

For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages . Note that a '+', '#', or '-' in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status.

Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial .

- **Note 1:** Junction temperature greater than +125°C degrades operating lifetimes.

### Electrical Characteristics

(V IN  = V EN/UVLO = 24V, R RT = 40.2kΩ (500kHz), C VCC  = 2.2µF, V PGND = V SGND = V MODE  = V SYNC  = 0V, LX = SS = RESET = open, V BST  to V LX  = 5V, V FB  = 1V, T A  = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25°C. All voltages are referenced to SGND, unless otherwise noted.) (Note 2)

**Electrical Characteristics** ([table-02-p2-spec.csv](max17504/tables/table-02-p2-spec.csv), p. 2)

| PARAMETER | SYMBOL | CONDITIONS | MIN | TYP | MAX | UNITS |
|---|---|---|---|---|---|---|
| **INPUT SUPPLY (V_IN)** |  |  |  |  |  |  |
| **INPUT SUPPLY (V_IN)** |  |  |  |  |  |  |
| Input Voltage Range | V_IN |  | 4.5 |  | 60 | V |
| Input Shutdown Current | I_IN-SH | V_EN/UVLO = 0V (shutdown mode) |  | 2.8 | 4.5 | µA |
| Input Quiescent Current | I_Q_PFM | V_FB = 1V, MODE = RT= open |  | 118 |  | µA |
| Input Quiescent Current | I_Q_PFM | V_FB = 1V, MODE = open |  | 162 |  | µA |
| Input Quiescent Current | I_Q_DCM | DCM mode, V_LX = 0.1V |  | 1.16 | 1.8 | mA |
| Input Quiescent Current | I_Q_PWM | Normal switching mode, f_SW = 500kHz, V_FB = 0.8V |  | 9.5 |  | mA |
| **ENABLE/UVLO (EN/UVLO)** |  |  |  |  |  |  |
| **ENABLE/UVLO (EN/UVLO)** |  |  |  |  |  |  |
| EN/UVLO Threshold | V_ENR | V_EN/UVLO rising | 1.19 | 1.215 | 1.24 | V |
| EN/UVLO Threshold | V_ENF | V_EN/UVLO falling | 1.068 | 1.09 | 1.111 | V |
| EN/UVLO Input Leakage Current | I_EN | V_EN/UVLO = 0V, T_A = +25°C | -50 | 0 | +50 | nA |
| **LDO** |  |  |  |  |  |  |
| **LDO** |  |  |  |  |  |  |
| V_CC Output Voltage Range | V_CC | 6V < V_IN < 60V, I_VCC = 1mA | 4.75 | 5 | 5.25 | V |
| V_CC Output Voltage Range | V_CC | 1mA ≤ I_VCC ≤ 25mA | 4.75 | 5 | 5.25 | V |
| V_CC Current Limit | I_VCC-MAX | V_CC = 4.3V, V_IN = 6V | 26.5 | 54 | 100 | mA |
| V_CC Dropout | V_CC-DO | V_IN = 4.5V, I_VCC = 20mA | 4.2 |  |  | V |
| V_CC UVLO | V_CC_UVR | V_CC rising | 4.05 | 4.2 | 4.3 | V |
| V_CC UVLO | V_CC_UVF | V_CC falling | 3.65 | 3.8 | 3.9 | V |
| **POWER MOSFET AND BST DRIVER** |  |  |  |  |  |  |
| **POWER MOSFET AND BST DRIVER** |  |  |  |  |  |  |
| High-Side nMOS On-Resistance | R_DS-ONH | I_LX = 0.3A |  | 165 | 325 | mΩ |
| Low-Side nMOS On-Resistance | R_DS-ONL | I_LX = 0.3A |  | 80 | 150 | mΩ |
| LX Leakage Current | I_LX_LKG | V_LX = V_IN - 1V, V_LX = V_PGND + 1V, T_A = +25°C | -2 |  | +2 | µA |
| **SOFT-START (SS)** |  |  |  |  |  |  |
| **SOFT-START (SS)** |  |  |  |  |  |  |
| Charging Current | I_SS | V_SS = 0.5V | 4.7 | 5 | 5.3 | µA |
| **FEEDBACK (FB)** |  |  |  |  |  |  |
| **FEEDBACK (FB)** |  |  |  |  |  |  |
| FB Regulation Voltage | V_FB_REG | MODE = SGND or MODE = V_CC | 0.89 | 0.9 | 0.91 | V |
| FB Regulation Voltage | V_FB_REG | MODE = open | 0.89 | 0.915 | 0.936 | V |
| FB Input Bias Current | I_FB | 0 < V_FB < 1V, T_A = +25°C | -50 |  | +50 | nA |
| **MODE** |  |  |  |  |  |  |
| **MODE** |  |  |  |  |  |  |
| MODE Threshold | V_M-DCM | MODE = V_CC (DCM mode) | V_CC - 1.6 |  |  | V |
| MODE Threshold | V_M-PFM | MODE = open (PFM mode) |  | V_CC/2 |  | V |
| MODE Threshold | V_M-PWM | MODE = GND (PWM mode) |  |  | 1.4 | V |
| **CURRENT LIMIT** |  |  |  |  |  |  |
| **CURRENT LIMIT** |  |  |  |  |  |  |
| Peak Current-Limit Threshold | I_PEAK-LIMIT |  | 4.4 | 5.1 | 5.85 | A |
| Runaway Current-Limit Threshold | I_RUNAWAY-LIMIT |  | 4.9 | 5.7 | 6.7 | A |
| Valley Current-Limit Threshold | I_SINK-LIMIT | MODE = open or MODE = V_CC | -0.16 | 0 | +0.16 | A |
| Valley Current-Limit Threshold | I_SINK-LIMIT | MODE = GND |  | -1.8 |  | A |
| PFM Current-Limit Threshold | I_PFM | MODE = open | 0.6 | 0.75 | 0.9 | A |
| **RT AND SYNC** |  |  |  |  |  |  |
| **RT AND SYNC** |  |  |  |  |  |  |
| Switching Frequency | f_SW | R_RT = 210kΩ | 90 | 100 | 110 | kHz |
| Switching Frequency | f_SW | R_RT = 102kΩ | 180 | 200 | 220 | kHz |
| Switching Frequency | f_SW | R_RT = 40.2kΩ | 475 | 500 | 525 | kHz |
| Switching Frequency | f_SW | R_RT = 8.06kΩ | 1950 | 2200 | 2450 | kHz |
| Switching Frequency | f_SW | R_RT = OPEN | 460 | 500 | 540 | kHz |
| SYNC Frequency Capture Range |  | f_SW set bt R_RT | 1.1 x f_SW |  | 1.4 x f_SW | kHz |
| SYNC Pulse Width |  |  | 50 |  |  | ns |
| SYNC Threshold | V_IH |  | 2.1 |  |  | V |
| SYNC Threshold | V_IL |  |  |  | 0.8 | V |
| V_FB Undervoltage Trip Level to Cause Hiccup | V_FB-HICF |  | 0.56 | 0.58 | 0.6 | V |
| HICCUP Timeout |  | (Note 3) |  | 32768 |  | Cycles |
| Minimum On-Time | t_ON-MIN | MAX17504 |  |  | 135 | ns |
| Minimum On-Time | t_ON-MIN | MAX17504S |  | 55 | 80 | ns |
| Minimum Off-Time | t_OFF-MIN |  | 140 |  | 160 | ns |
| LX Dead Time |  |  |  | 5 |  | ns |
| **RESET** |  |  |  |  |  |  |
| R̅E̅S̅E̅T̅ Output Level Low |  | I_R̅E̅S̅E̅T̅ = 1mA |  |  | 0.4 | V |
| R̅E̅S̅E̅T̅ Output Leakage Current |  | T_A = T_J = +25ºC, V_R̅E̅S̅E̅T̅ = 5.5V | -0.1 |  | +0.1 | µA |
| V_OUT Threshold for R̅E̅S̅E̅T̅ Assertion | V_FB-OKF | V_FB falling | 90.5 | 92 | 94 | % |
| V_OUT Threshold for R̅E̅S̅E̅T̅ Deassertion | V_FB-OKR | V_FB rising | 93.8 | 95 | 97.2 | % |
| R̅E̅S̅E̅T̅ Deassertion Delay After FB Reaches 95% Regulation |  |  |  | 1024 |  | Cycles |
| **THERMAL SHUTDOWN** |  |  |  |  |  |  |
| Thermal Shutdown Threshold |  | Temperature rising |  | 165 |  | °C |
| Thermal Shutdown Hysteresis |  |  |  | 10 |  | °C |

- **Note 2:** All limits are 100% tested at +25°C. Limits over temperature are guaranteed by design.

- **Note 3:** See the Overcurrent Protection/HICCUP Mode section for more details.

### Typical Operating Characteristics

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

### Typical Operating Characteristics (continued)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

2ms/div

2ms/div

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

50mV/div

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

MAX17504S 3.3V OUTPUT

LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A

(PWM MODE, FIGURE 6 CIRCUIT)

MODE = SGND

S/div

1mS/div toc27a

VOUT

VOUT

AWWWW

2mS/div MODE = OPEN

100mV/div

1A/div

100mV/div

1A/div

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

(V IN  = V EN/UVLO  = 24V, V PGND = V SGND = 0V, C VIN  = 2 x 2.2µF , C VCC  = 2.2µF , C BST  = 0.1µF , C SS = 12,000pF, RT = MODE = open, T A  = T J = -40°C to +125°C, unless otherwise noted. Typical values are at T A  = +25° C. All voltages are referenced to SGND, unless otherwise noted.)

### Pin Configuration

### Pin Description

**Pin Description** ([table-03-p15-pin.csv](max17504/tables/table-03-p15-pin.csv), p. 15)

| NUMBER | NAME | TYPE | DESCRIPTION |
|---|---|---|---|
| 1, 2, 3 | V_IN |  | Power-Supply Input. 4.5V to 60V input supply range. Connect the V_IN pins together. Decouple to PGND with two 2.2µF capacitors; place the capacitors close to the V_IN and PGND pins. Refer to the MAX17504/MAX17504S EV kit data sheet for a layout example. |
| 4 | EN/UVLO |  | Enable/Undervoltage Lockout. Drive EN/UVLO high to enable the output voltage. Connect to the center of the resistor-divider between V_IN and SGND to set the input voltage at which the MAX17504/MAX17504S turns on. Pull up to V_IN for always on operation. |
| 5 | R̅E̅S̅E̅T̅ |  | Open-Drain R̅E̅S̅E̅T̅ Output. The R̅E̅S̅E̅T̅ output is driven low if FB drops below 92% of its set value. R̅E̅S̅E̅T̅ goes high 1024 clock cycles after FB rises above 95% of its set value. |
| 6 | SYNC |  | The device can be synchronized to an external clock using this pin. See the External Frequency Synchronization section for more details. |
| 7 | SS |  | Soft-Start Input. Connect a capacitor from SS to SGND to set the soft-start time. |
| 8 | CF |  | At switching frequencies lower than 500kHz, connect a capacitor from CF to FB. Leave CF open if the switching frequency is equal to or more than 500kHz. See the Loop Compensation section for more details. |
| 9 | FB |  | Feedback Input. Connect FB to the center tap of an external resistor-divider from the output to SGND to set the output voltage. See the Adjusting Output Voltage section for more details. |
| 10 | RT |  | Connect a resistor from RT to SGND to set the regulator's switching frequency. Leave RT open for the default 500kHz frequency. See the Setting the Switching Frequency (RT) section for more details. |
| 11 | MODE |  | MODE configures the MAX17504/MAX17504S to operate in PWM, PFM or DCM modes of operation. Leave MODE unconnected for PFM operation (pulse skipping at light loads). Connect MODE to SGND for constant-frequency PWM operation at all loads. Connect MODE to V_CC for DCM operation. See the MODE Setting section for more details. |
| 12 | V_CC |  | 5V LDO Output. Bypass V_CC with a 2.2µF ceramic capacitance to SGND. |
| 13 | SGND |  | Analog Ground |
| 14, 15, 16 | PGND |  | Power Ground. Connect the PGND pins externally to the power ground plane. Connect the SGND and PGND pins together at the ground return path of the V_CC bypass capacitor. Refer to the MAX17504/MAX17504S EV kit data sheet for a layout example. |
| 17, 18, 19 | LX |  | Switching Node. Connect LX pins to the switching side of the inductor. |
| 20 | BST |  | Boost Flying Capacitor. Connect a 0.1µF ceramic capacitor between BST and LX. |
| — | EP |  | Exposed pad. Connect to the SGND pin. Connect to a large copper plane below the IC to improve heat dissipation capability. Add thermal vias below the exposed pad. Refer to the MAX17504/MAX17504S EV kit data sheet for a layout example. |

### Pin Description (continued)

*Continuation of **Pin Description** — rows included in the table above.*

### Block Diagram

### Detailed Description

The MAX17504/MAX17504S high-efficiency, high-voltage, synchronously  rectified  step-down  converter  with  dual integrated MOSFETs operates over a 4.5V to 60V input. It delivers up to 3.5A and 0.9V to 90% V IN  output voltage. Built-in  compensation  across  the  output  voltage  range eliminates the need for external components. The feedback (FB) regulation accuracy over -40°C to +125°C is ±1.1%. The  device  features a  peak-current-mode  control architecture. An internal transconductance error amplifier  produces  an  integrated  error  voltage  at  an internal  node  that  sets  the  duty  cycle  using  a  PWM comparator, a high-side current-sense amplifier, and a slope-compensation generator. At each rising edge of the clock, the high-side MOSFET turns on and remains on until either the appropriate or maximum duty cycle is reached, or the peak current limit is detected. During the high-side MOSFET's on-time, the inductor current ramps  up.  During  the  second  half  of  the  switching cycle, the high-side MOSFET turns off and the low-side MOSFET  turns  on.  The  inductor  releases  the  stored energy as its current ramps down and provides current to the output.

The device features a MODE pin that can be used to operate the device in PWM, PFM, or DCM control schemes. The device  integrates  adjustable-input  undervoltage  lockout, adjustable soft-start, open RESET , and external frequency synchronization features. The MAX17504S  offers a lower  minimum  on-time  that  allows  for  higher  switching frequencies and a smaller solution size.

### Mode Selection (MODE)

The  logic  state  of  the  MODE  pin  is  latched  when  V CC and  EN/UVLO  voltages  exceed  the  respective  UVLO rising  thresholds  and  all  internal  voltages  are  ready  to allow LX switching. If the MODE pin is open at power-up, the  device  operates  in  PFM  mode  at  light  loads.  If  the MODE pin is grounded at power-up, the device operates in  constant-frequency  PWM  mode  at  all  loads.  Finally, if  the  MODE  pin  is  connected  to  V CC   at  power-up,  the device operates in constant-frequency DCM mode at light loads. State changes on the MODE pin are ignored during normal operation.

### PWM Mode Operation

In PWM mode, the inductor current is allowed to go negative. PWM  operation  provides  constant  frequency  operation  at all loads, and is useful in applications sensitive to switching frequency. However, the PWM mode of operation gives lower efficiency at light loads compared to PFM and DCM modes of operation.

### PFM Mode Operation

PFM mode of operation disables negative inductor current and  additionally  skips  pulses  at  light  loads  for  high efficiency. In PFM mode, the inductor current is forced to a fixed peak of 750mA every clock cycle until the output rises to 102.3% of the nominal voltage. Once the output reaches 102.3% of the nominal voltage, both the high-side and low-side FETs are turned off and the device enters hibernate operation until the load discharges the output to 101.1% of the nominal voltage. Most of the internal blocks are  turned  off  in  hibernate  operation  to  save  quiescent current. After the output falls below 101.1% of the nominal voltage,  the  device  comes  out  of  hibernate  operation, turns  on  all  internal  blocks,  and  again  commences  the process of delivering pulses of energy to the output until it reaches 102.3% of the nominal output voltage.

The advantage of the PFM mode is higher efficiency at light loads because of lower quiescent current drawn from supply. The disadvantage is that the output-voltage ripple is higher compared to PWM or DCM modes of operation and switching frequency is not constant at light loads.

### DCM Mode Operation

DCM  mode  of  operation  features  constant  frequency operation down to lighter loads than PFM mode, by not skipping  pulses  but  only  disabling  negative  inductor current  at  light  loads.  DCM  operation  offers  efficiency performance that lies between PWM and PFM modes.

### Linear Regulator (V CC)

An internal linear regulator (V CC ) provides a 5V nominal supply  to  power  the  internal  blocks  and  the  low-side MOSFET driver. The output of the linear regulator (V CC ) should  be  bypassed  with  a  2.2µF  ceramic  capacitor to  SGND.  The  MAX17504/MAX17504S  employs  an undervoltage  lockout  circuit  that  disables  the  internal linear regulator when V CC  falls below 3.8V (typ).

### Setting the Switching Frequency (RT)

The switching frequency of the MAX17504/MAX17504S can  be  programmed  from  100kHz  to  2.2MHz  by  using a  resistor  connected  from  RT  to  SGND.  The  switching frequency (f SW ) is related to the resistor connected at the RT pin (R RT ) by the following equation:

![Equation as printed (p. 17)](max17504/figures/max17504-eq01.png)

$$R_{RT} \cong \frac{21 \times 10^{3}}{f_{SW}} - 1.7$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where R RT  is in kΩ and f SW is in kHz. Leaving the RT pin open causes the device to operate at the default switching frequency of 500kHz. See Table 1 for RT resistor values for a few common switching frequencies.

### Table 1. Switching Frequency vs. RT Resistor

**Table 1. Switching Frequency vs. RT Resistor** ([table-04-p18-data.csv](max17504/tables/table-04-p18-data.csv), p. 18)

| SWITCHING FREQUENCY (kHz) | RT RESISTOR (kΩ) |
|---|---|
| 500 | OPEN |
| 100 | 210 |
| 200 | 102 |
| 400 | 49.9 |
| 1000 | 19.1 |
| 2200 | 8.06 |

### Operating Input Voltage Range

The minimum and maximum operating input voltages for a given output voltage should be calculated as follows:

![Equation as printed (p. 18)](max17504/figures/max17504-eq02.png)

$$V_{IN(MIN)} = \frac{V_{OUT} + (I_{OUT(MAX)} \times (R_{DCR} + 0.15))}{1 - (f_{SW(MAX)} \times t_{OFF(MAX)})} + (I_{OUT(MAX)} \times 0.175)$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

![Equation as printed (p. 18)](max17504/figures/max17504-eq03.png)

$$V_{IN ( MAX )} = \frac{V_{OUT}}{f_{SW ( MAX )} \times t_{ON ( MIN )}}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where V OUT  is the steady-state output voltage, I OUT(MAX) is the maximum load current, R DCR is the DC resistance of  the  inductor,  f SW(MAX)   is  the  maximum  switching frequency, t OFF(MAX)  is the worst-case minimum switch off-time (160ns), and t ON(MIN)  is the worst-case minimum switch  on-time  (135ns  for  the  MAX17504,  80ns  for  the MAX17504S).

### External Frequency Synchronization (SYNC)

The internal oscillator of the MAX17504/MAX17504S can be synchronized to an external clock signal on the SYNC pin.  The  external  synchronization  clock  frequency  must be between 1.1 x f SW  and 1.4 x f SW , where f SW  is the frequency programmed by the RT resistor. The minimum external  clock  pulse-width  high  should  be  greater  than 50ns.  See  the  RT  and  SYNC  section  in  the Electrical Characteristics table for details.

### Overcurrent Protection/HICCUP Mode

The  MAX17504/MAX17504S  is  provided  with  a  robust overcurrent  protection  scheme  that  protects  the  device under  overload  and  output  short-circuit  conditions.  A cycle-by-cycle  peak  current  limit  turns  off  the  high-side MOSFET whenever the high-side switch current exceeds an internal limit of 5.1A (typ). A runaway current limit on the  high-side  switch  current  at  5.7A  (typ)  protects  the device  under  high  input  voltage,  short-circuit  conditions when  there  is  insufficient  output  voltage  available  to restore the inductor current that was built up during the ON period of the  step-down  converter.  One  occurrence of  the  runaway  current  limit  triggers  a  hiccup  mode.  In addition,  if  due  to  a  fault  condition,  feedback  voltage drops to 0.58V (typ) anytime after soft-start is complete, hiccup mode is triggered. In hiccup mode, the converter is protected by suspending switching for a hiccup timeout period  of  32,768  clock  cycles.  Once  the  hiccup  timeout period  expires,  soft-start  is  attempted  again.  Note  that when soft-start is attempted under an overload condition, if  feedback  voltage  does  not  exceed  0.58V,  the  device switches  at  half  the  programmed  switching  frequency. Hiccup mode of operation ensures low power dissipation under output short-circuit conditions.

### RESET Output

The MAX17504/MAX17504S includes a RESET comparator  to  monitor  the  output  voltage.  The  opendrain RESET output requires an external pullup resistor. RESET goes  high  (high-impedance)  1024  switching cycles  after  the  regulator  output  increases  above  95% of the designed nominal regulated voltage. RESET goes low when the regulator output voltage drops to below 92% of the nominal regulated voltage. RESET also goes low during thermal shutdown.

### Prebiased Output

When the MAX17504/MAX17504S starts into a prebiased output, both the high-side and the low-side switches are turned off so that the converter does not sink current from the output. High-side and low-side switches do not start switching until the PWM comparator commands the first PWM pulse,  at  which  point  switching  commences.  The output voltage is then smoothly ramped up to the target value in alignment with the internal reference.

### Thermal-Shutdown Protection

Thermal-shutdown protection limits total power dissipation in the  MAX17504/MAX17504S. When  the junction temperature  of  the  device  exceeds  +165°C,  an  on-chip thermal sensor shuts down the device, allowing the device to  cool.  The  thermal  sensor  turns  the  device  on  again after  the  junction  temperature  cools  by  10 °C.  Soft-start resets  during  thermal  shutdown.  Carefully  evaluate  the total power dissipation (see the Power Dissipation section) to  avoid  unwanted triggering of the thermal shutdown in normal operation.

### Applications Information

### Input Capacitor Selection

The  input  filter  capacitor  reduces  peak  currents  drawn from  the  power  source  and  reduces  noise  and  voltage ripple  on  the  input  caused  by  the  circuit's  switching. The  input  capacitor  RMS  current  requirement  (I RMS )  is defined by the following equation:

![Equation as printed (p. 19)](max17504/figures/max17504-eq04.png)

$$I_{RMS} = I_{OUT(MAX)} \times \frac{\sqrt{V_{OUT} \times (V_{IN} - V_{OUT})}}{V_{IN}}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where, I OUT(MAX)  is the maximum load current. I RMS has a  maximum  value  when  the  input  voltage  equals  twice the  output  voltage  (V IN   =  2  x  V OUT ),  so  I RMS(MAX) = I OUT(MAX) /2.

Choose an input capacitor that exhibits less than +10°C temperature  rise  at  the  RMS  input  current  for  optimal long-term reliability. Use low-ESR ceramic capacitors with high ripple current capability at the input. X7R capacitors are  recommended  in  industrial  applications  for  their temperature  stability.  Calculate  the  input  capacitance using the following equation:

![Equation as printed (p. 19)](max17504/figures/max17504-eq05.png)

$$C_{IN} = \frac{I_{OUT ( MAX )} \times D \times ( 1 - D )}{\eta \times f_{SW} \times \Delta V_{IN}}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where  D  =  V OUT /V IN   is  the  duty  ratio  of  the  controller, fSW is the switching frequency, ΔV IN  is the allowable input voltage ripple, and E is the efficiency.

In  applications  where  the  source  is  located  distant from  the  MAX17504/MAX17504S  input,  an  electrolytic capacitor  should  be  added  in  parallel  to  the  ceramic capacitor  to  provide  necessary  damping  for  potential oscillations caused by the inductance of the longer input power path and input ceramic capacitor.

### Inductor Selection

Three  key  inductor  parameters  must  be  specified  for operation  with  the  MAX17504/MAX17504S:  inductance value  (L),  inductor  saturation  current  (I SAT ),  and  DC resistance  (R DCR ).  The  switching  frequency  and  output voltage determine the inductor value as follows:

![Equation as printed (p. 19)](max17504/figures/max17504-eq06.png)

$$L = \frac{V_{OUT}}{f_{SW}}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where V OUT  and f SW  are nominal values.

Select  a  low-loss  inductor  closest  to  the  calculated value with acceptable dimensions and having the lowest possible  DC  resistance.  The  saturation  current  rating (I SAT ) of the inductor must be high enough to ensure that saturation  can  occur  only  above  the  peak  current-limit value of 5.1A.

### Output Capacitor Selection

X7R ceramic output capacitors are preferred due to their stability  over  temperature  in  industrial  applications.  The output capacitors are usually sized to support a step load of 50% of the maximum output current in the application, so the output voltage deviation is contained to 3% of the output  voltage  change.  The  minimum  required  output capacitance can be calculated as follows:

![Equation as printed (p. 19)](max17504/figures/max17504-eq07.png)

$$CouT = \frac{1}{2} \times \frac{I_{STEP} \times t_{RESPONSE}}{\Delta V_{OUT}} \\ t_{RESPONSE} \cong ( \frac{0.33}{f_{C}} + \frac{1}{f_{SW}} ) \\$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where I STEP  is the load current step, t RESPONSE is  the response time of the controller, D VOUT is the allowable output  voltage  deviation,  f C   is  the  target  closed-loop crossover frequency, and f SW  is the switching frequency. For  the  MAX17504,  select  f C   to  be  1/9th  of  f SW   if  the switching frequency is less than or equal to 500kHz. If the switching frequency is more than 500kHz, select f C to be 55kHz. For the MAX17504S, select f C to be 1/10th of f SW if the switching frequency is less than or equal to 1MHz. If  the  switching frequency is more than 1MHz, select f C to be 100kHz.

Derating of ceramic capacitors with DC-voltage must be considered while selecting the output capacitor. Derating curves  are  available  from  all  major  ceramic  capacitor vendors.

### Soft-Start Capacitor Selection

The MAX17504/MAX17504S implements adjustable softstart  operation  to  reduce  inrush  current.  A  capacitor connected  from  the  SS  pin  to  SGND  programs  the soft-start  time.  The  selected  output  capacitance  (C SEL ) and  the  output  voltage  (V OUT )  determine  the  minimum required soft-start capacitor as follows:

![Equation as printed (p. 20)](max17504/figures/max17504-eq08.png)

$$C_{SS} \geq 28 \times 10^{-6} \times C_{SEL} \times V_{OUT}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

The  soft-start time  (t SS ) is  related  to  the  capacitor connected at SS (C SS ) by the following equation:

![Equation as printed (p. 20)](max17504/figures/max17504-eq09.png)

$$t_{SS} = C_{SS} / ( 5.55 \times 10^{-6} )$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

For  example,  to  program  a  2ms  soft-start  time,  a  12nF capacitor should be connected from the SS pin to SGND.

### Setting the Input Undervoltage Lockout Level

The  MAX17504/MAX17504S  offers  an  adjustable  input undervoltage  lockout  level.  Set  the  voltage  at  which MAX17504/MAX17504S turns ON, with a resistive voltagedivider connected from V IN to  SGND. Connect the center node of the divider to EN/UVLO.

Choose R1 to be 3.3MΩ and then calculate R2 as follows:

![Equation as printed (p. 20)](max17504/figures/max17504-eq10.png)

$$R 2 = \frac{R 1 \times 1.215}{( V_{INU} - 1.215 )}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where  V INU   is  the  voltage  at  which  the  MAX17504/ MAX17504S is required to turn ON. Ensure that V INU  is higher than 0.8 x V OUT . If the EN/UVLO pin is driven from an external signal source, a series resistance of minimum 1kΩ  is  recommended  to  be  placed  between  the  signal source output and the EN/UVLO pin, to reduce voltage ringing on the line.

### Loop Compensation

The MAX17504/MAX17504S is internally loop compensated. However, if the switching frequency is less than 500kHz, connect a 0402 capacitor, C6, between the CF pin and the FB pin. Use Table 2 to select the value of C6.

### Adjusting Output Voltage

Set  the  output  voltage  with  a  resistive  voltage-divider connected  from  the  positive  terminal  of  the  output capacitor (V OUT )  to  SGND (see Figure 2). Connect the center node of the divider to the FB pin. Use the following procedure to choose the resistive voltage-divider values: Calculate resistor R3 from the output to FB as follows:

![Equation as printed (p. 20)](max17504/figures/max17504-eq11.png)

$$R 3 = \frac{216 \times 10^{3}}{f_{C} \times C_{OUT}}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where  R3  is  in  kΩ ,  crossover  frequency  f C is  in  kHz, and output capacitor C OUT  is in µF. For the MAX17504, choose f C  to be 1/9th of the switching frequency, f SW , if the switching frequency is less than or equal to 500kHz. If the switching frequency is more than 500kHz, select f C to be 55kHz. For the MAX17504S, select f C to be 1/10th of  f SW   if  the  switching  frequency  is  less  than  or  equal to 1MHz. If the switching frequency is more than 1MHz, select f C to be 100kHz.

Calculate resistor R4 from FB to SGND as follows:

![Equation as printed (p. 20)](max17504/figures/max17504-eq12.png)

$$R 4 = \frac{R 3 \times 0.9}{( V_{OUT} - 0.9 )}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

### Table 2. C6 Capacitor Value at Various Switching Frequencies

**Table 2. C6 Capacitor Value at Various Switching Frequencies** ([table-05-p20-data.csv](max17504/tables/table-05-p20-data.csv), p. 20)

| SWITCHING FREQUENCY RANGE (kHz) | C6 (pF) |
|---|---|
| 200 to 300 | 2.2 |
| 300 to 400 | 1.2 |
| 400 to 500 | 0.75 |

### Power Dissipation

At a particular operating condition, the power losses that lead  to  temperature  rise  of  the  part  are  estimated  as follows:

![Equation as printed (p. 21)](max17504/figures/max17504-eq13.png)

$$P_{LOSS} = ( P_{OUT} \times ( \frac{1}{\eta} - 1 ) ) - \left( I_{OUT} \right^{2} \times R_{DCR} \ \right) \\ P_{OUT} = V_{OUT} \times I_{OUT}$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

where P OUT is  the  total  output  power,  η  is  the  efficiency of  the  converter,  and  R DCR is  the  DC  resistance  of  the inductor. (See the Typical Operating Characteristics for more information on efficiency at typical operating conditions).

For a multilayer board, the thermal performance metrics for the package are given below:

![Equation as printed (p. 21)](max17504/figures/max17504-eq14.png)

$$\theta_{JA} = 30^{\circ} C / W$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

![Equation as printed (p. 21)](max17504/figures/max17504-eq15.png)

$$\theta_{JC} = 2 \circ C$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

![Equation as printed (p. 21)](max17504/figures/max17504-eq16.png)

$$\theta_{JA} = 30^{\circ} C / W \\ \theta_{JC} = 2^{\circ} C / W$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

The junction temperature of the MAX17504/MAX17504S can  be  estimated  at  any  given  maximum  ambient temperature (T A\_MAX ) from the equation below:

![Equation as printed (p. 21)](max17504/figures/max17504-eq17.png)

$$T_{\sqcup_{-} MAX} = T_{A_{-} MAX} + ( \theta_{JA} \times P_{LOSS} )$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

If  the  application  has  a  thermal  management  system that  ensures  that  the  exposed  pad  of  the  MAX17504/ MAX17504S is maintained at a given temperature (T EP\_ MAX )  by  using  proper  heat  sinks,  then  the  junction temperature  of  the  MAX17504/MAX17504S  can  be estimated  at  any  given  maximum  ambient  temperature from the equation below:

![Equation as printed (p. 21)](max17504/figures/max17504-eq18.png)

$$T_{J_{-} MAX} = T_{EP_{-} MAX} + ( \theta_{JC} \times P_{LOSS} )$$

*LaTeX transcription of the equation above, checked against the symbols printed on the page.*

Junction  temperature  greater  than  +125°C  degrades operating lifetimes.

### PCB Layout Guidelines

All  connections  carrying  pulsed  currents  must  be  very short and as wide as possible. The inductance of these connections must be kept to an absolute minimum due to the high di/dt of the currents. Since inductance of a current carrying loop is proportional to the area enclosed by the loop,  if  the  loop  area  is  made  very  small,  inductance  is reduced.  Additionally,  small  current  loop  areas  reduce radiated EMI.

A ceramic input filter capacitor should be placed close to the VIN  pins of the IC. This eliminates as much trace inductance effects as possible and give the IC a cleaner voltage supply. A bypass capacitor for the V CC  pin also should be placed close to the pin to reduce effects of trace impedance.

When  routing  the  circuitry  around  the  IC,  the  analog small-signal ground and the power ground for switching currents must be kept separate. They should be connected together  at  a  point  where  switching  activity  is  at  a minimum, typically the return terminal of the V CC  bypass capacitor.  This  helps  keep  the  analog  ground  quiet. The  ground  plane  should  be  kept  continuous/unbroken as  far  as  possible.  No  trace  carrying  high  switching current should be placed directly over any ground plane discontinuity.

PCB layout also affects the thermal performance of the design. A number of thermal vias that connect to a large ground plane should be provided under the exposed pad of the part, for efficient heat dissipation.

For  a  sample  layout  that  ensures  first  pass  success, refer to the MAX17504 evaluation kit layout available at www.maximintegrated.com .

### Recommended Component Placement for MAX17504/MAX17504S


### Ordering Information

**Ordering Information** ([table-06-p25-data.csv](max17504/tables/table-06-p25-data.csv), p. 25)

| PART | PIN-PACKAGE |
|---|---|
| MAX17504ATP+ | 20 TQFN-EP* 5mm x 5mm |
| MAX17504SATP+ | 20 TQFN-EP* 5mm x 5mm |

- Note: All devices operate over the temperature range of -40°C to +125°C, unless otherwise noted.
- +: Denotes a lead(Pb)-free/RoHS-compliant package.
- **\*:** EP = Exposed pad.

Note:

All devices operate over the temperature range of -40ºC

to +125ºC, unless otherwise noted.

### Chip Information

PROCESS: BiCMOS

### Revision History

**Revision History** ([table-07-p26-data.csv](max17504/tables/table-07-p26-data.csv), p. 26)

| REVISION NUMBER | REVISION DATE | DESCRIPTION | PAGES CHANGED |
|---|---|---|---|
| 0 | 11/13 | Initial release | — |
| 1 | 2/14 | Updated TOC32, TOC33, and Typical Application Circuit figures | 9, 16, 17 |
| 2 | 10/16 | Added MAX17504S to data sheet, updated junction temperature, and added TOCs | 1-17 |
| 3 | 5/17 | Removed 17504S from data sheet, corrected part numbers in General Description, Benefits and Features, Detailed Description, Operating Input Voltage Range sections, updated TOCs 1a, 5, 5a, 6, 7a, 12, 12a, 13, 13a, 14a, 15a, 16a, 17a, 18a, 19a, 20a, 21a, 22, 22a, 23, 23a, 24a, 25a, 26a, 27a, 30a, 32a, Figures 3, 4, 5, and 6, removed Recommended Component Placement for MAX17504/MAX17504S | 1–26 |

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com.

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Character -istics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.

## Additional Figures

![other (p. 1)](max17504/figures/max17504-f000.png)

![MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f001.png)

*MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f002.png)

*MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f003.png)

*MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f004.png)

*MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 5 CIRCUIT)*

![MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f005.png)

*MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PWM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f006.png)

*MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f007.png)

*MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 4 CIRCUIT)*

![MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f008.png)

*MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (PFM MODE, FIGURE 6 CIRCUIT)*

![MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f009.png)

*MAX17504 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f010.png)

*MAX17504 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f011.png)

*MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f012.png)

*MAX17504S 5V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f013.png)

*MAX17504S 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT (DCM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f014.png)

*MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 5 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f015.png)

*MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 4 CIRCUIT)*

![MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f016.png)

*MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PWM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f017.png)

*MAX17504S 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f018.png)

*MAX17504S 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 6 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f019.png)

*MAX17504 5V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f020.png)

*MAX17504 3.3V OUTPUT LOAD AND LINE REGULATION (PFM MODE, FIGURE 4 CIRCUIT)*

![SWITCHING FREQUENCY vs. RT RESISTANCE](max17504/figures/max17504-f021.png)

*SWITCHING FREQUENCY vs. RT RESISTANCE*

![MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f022.png)

*MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO, (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f023.png)

*MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO, (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f024.png)

*MAX17504 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f025.png)

*MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f026.png)

*MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f027.png)

*MAX17504S 5V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f028.png)

*MAX17504 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 4 CIRCUIT)*

![MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f029.png)

*MAX17504S 3.3V OUTPUT SOFT-START/SHUTDOWN FROM EN/UVLO (PFM MODE, 5mA LOAD CURRENT, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f030.png)

*MAX17504S 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f031.png)

*MAX17504S 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 6 CIRCUIT)*

![MAX17504 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f032.png)

*MAX17504 5V OUTPUT SOFT-START WITH 2.5V PREBIAS (PWM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PFM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f033.png)

*MAX17504 3.3V OUTPUT SOFT-START WITH 2.5V PREBIAS (PFM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f034.png)

*MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)*

![MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PWM MODE, NO LOAD, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f035.png)

*MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PWM MODE, NO LOAD, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f036.png)

*MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mALOAD, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f037.png)

*MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mALOAD, FIGURE 3 CIRCUIT)*

![MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 25mALOAD, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f038.png)

*MAX17504 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 25mALOAD, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (NO LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f039.png)

*MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (NO LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mA LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f040.png)

*MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (PFM MODE, 25mA LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 150mA LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f041.png)

*MAX17504S 5V OUTPUT STEADY-STATE SWITCHING WAVEFORMS (DCM MODE, 150mA LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 1.7`5ATO 3.5A (PWM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f042.png)

*MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 1.7`5ATO 3.5A (PWM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75ATO 3.5A (PWM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f043.png)

*MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75ATO 3.5A (PWM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f044.png)

*MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f045.png)

*MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f046.png)

*MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 1.75A TO 3.5A (PWM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f047.png)

*MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 5 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f048.png)

*MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f049.png)

*MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f050.png)

*MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5mATO 1.75A (PFM MODE, FIGURE 4 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f051.png)

*MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 5 CIRCUIT)*

![MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f052.png)

*MAX17504 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f053.png)

*MAX17504 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 4 CIRCUIT)*

![MAX17504 5V OUTPUT OVERLOAD PROTECTION (FIGURE 3 CIRCUIT)](max17504/figures/max17504-f054.png)

*MAX17504 5V OUTPUT OVERLOAD PROTECTION (FIGURE 3 CIRCUIT)*

![MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f055.png)

*MAX17504S 5V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f056.png)

*MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 50mATO 1.75A (DCM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 5V OUTPUT OVERLOAD PROTECTION (FIGURE 5 CIRCUIT)](max17504/figures/max17504-f057.png)

*MAX17504S 5V OUTPUT OVERLOAD PROTECTION (FIGURE 5 CIRCUIT)*

![MAX17504 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 700kHz (FIGURE 3 CIRCUIT)](max17504/figures/max17504-f058.png)

*MAX17504 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 700kHz (FIGURE 3 CIRCUIT)*

![MAX17504 5V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)](max17504/figures/max17504-f059.png)

*MAX17504 5V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 3 CIRCUIT)*

![MAX17504 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)](max17504/figures/max17504-f060.png)

*MAX17504 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 4 CIRCUIT)*

![MAX17504S 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 1.2MHz, (FIGURE 5 CIRCUIT)](max17504/figures/max17504-f061.png)

*MAX17504S 5V OUTPUT APPLICATION OF EXTERNAL CLOCK AT 1.2MHz, (FIGURE 5 CIRCUIT)*

![MAX17504S 5V OUTPUT 4 BODE PLOT (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)](max17504/figures/max17504-f062.png)

*MAX17504S 5V OUTPUT 4 BODE PLOT (3.5A LOAD CURRENT, FIGURE 5 CIRCUIT)*

![MAX17504S 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f063.png)

*MAX17504S 3.3V OUTPUT BODE PLOT (3.5A LOAD CURRENT, FIGURE 6 CIRCUIT)*

![pinout (p. 15)](max17504/figures/max17504-f064.png)

![block diagram (p. 16)](max17504/figures/max17504-f065.png)

![Figure 1. Setting the Input Undervoltage Lockout](max17504/figures/max17504-f066.png)

*Figure 1. Setting the Input Undervoltage Lockout*

![Figure 2. Setting the Output Voltage](max17504/figures/max17504-f067.png)

*Figure 2. Setting the Output Voltage*

![layout drawing (p. 22)](max17504/figures/max17504-f068.png)

![Figure 3. MAX17504 Typical Application Circuit for 5V Output, 500kHz Switching Frequency](max17504/figures/max17504-f069.png)

*Figure 3. MAX17504 Typical Application Circuit for 5V Output, 500kHz Switching Frequency*

![Figure 4. MAX17504 Typical Application Circuit for 3.3V Output, 500kHz Switching Frequency](max17504/figures/max17504-f070.png)

*Figure 4. MAX17504 Typical Application Circuit for 3.3V Output, 500kHz Switching Frequency*

![Figure 5. MAX17504S Typical Operating Circuit for 5V Output, 1MHz Switching Frequency](max17504/figures/max17504-f071.png)

*Figure 5. MAX17504S Typical Operating Circuit for 5V Output, 1MHz Switching Frequency*

![Figure 6. MAX17504S Typical Operating Circuit for 3.3V Output, 1MHz Switching Frequency](max17504/figures/max17504-f072.png)

*Figure 6. MAX17504S Typical Operating Circuit for 3.3V Output, 1MHz Switching Frequency*

![MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f073.png)

*MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM NO LOAD TO 1.75A (PWM MODE, FIGURE 6 CIRCUIT)*

![MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 6 CIRCUIT)](max17504/figures/max17504-f074.png)

*MAX17504S 3.3V OUTPUT LOAD CURRENT STEPPED FROM 5MA TO 1.75A (PFM MODE, FIGURE 6 CIRCUIT)*