LTC3307A

5V, 3A Synchronous Step-Down Silent Switcher in 2mm × 2mm LQFN

Data Sheet

Rev. B

Recommended for New Designs

Top

Overview

Features and Benefits
Product Details

Features and Benefits

Pin Compatible with LTC3308(4A) and LTC3309(6A)
High Efficiency: 8mΩ NMOS, 31mΩ PMOS
Programmable Frequency 1MHz to 3MHz

Tiny Inductor and Capacitors

Peak Current Mode Control

22ns Minimum On-Time
Wide Bandwidth, Fast Transient Response

Silent Switcher^® Architecture

Ultralow EMI Emissions

Low Ripple Burst Mode^® Operation with I_Q of 40µA
Safely Tolerates Inductor Saturation in Overload
V_IN Range: 2.25V to 5.5V
V_OUT Range: 0.5V to V_IN
V_OUT Accuracy: ±1% Over Temperature Range
Precision 400mV Enable Threshold, 1µA in Shutdown
Power Good, Internal Compensation and Soft Start
Thermally Enhanced 2mm × 2mm LQFN Package
AEC-Q100 Qualified for Automotive Applications

Product Details

The LTC3307A is a very small, high efficiency, low noise, monolithic synchronous 3A step-down DC/DC converter operating from a 2.25V to 5.5V input supply. Using constant frequency, peak current mode control at switching frequencies 1MHz to 3MHz and minimum on-time as low as 22ns, this regulator achieves fast transient response with small external components. Silent Switcher architecture minimizes EMI emissions.

The LTC3307A operates in forced continuous or pulse skip mode for low noise, or low-ripple Burst Mode operation for high efficiency at light loads, ideal for battery-powered systems. The IC regulates output voltages as low as 500mV. Other features include output overvoltage protection, short-circuit protection, thermal shutdown, clock synchronization, and up to 100% duty cycle operation for low dropout. The device is available in a low profile 12-lead 2mm × 2mm × 0.74mm LQFN package with exposed pad for low thermal resistance.

APPLICATIONS

Optical Networking, Servers, Telecom
Automotive, Industrial, Communications
Distributed DC Power Systems (POL)
FPGA, ASIC, µP Core Supplies
Battery Operated Systems

Product Categories

Power Management

Comparable Parts Click to see all in Parametric Search

Product Lifecycle Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (1)

DC2990A

LTC3307A | 5V Input to 1.2V Output at 3A Synchronous Step‑Down Silent Switcher Demo Circuit

DC2990A

View Detailed Evaluation Kit Information

Demonstration circuit 2990A features the LTC3307A 5V, 3A synchronous step-down Silent Switcher^® operating as a 2MHz, 3.3V to 1.2V 3A buck regulator. The LTC3307A supports adjustable output voltages from 0.5V to V_IN with operating frequencies from 1MHz up to 3MHz. The LTC3307A is a compact, ultralow emission, high efficiency, and high speed synchronous monolithic step-down switching regulator. A minimum on-time of 22ns enables high V_IN to low V_OUT conversion ratios at high frequencies.

The DC2990A operating mode may be selected as Burst, Skip or forced continuous (FC) mode. Setting JP1 to the FC/SYNC position will allow the LTC3307A to sync to a clock frequency from 1MHz to 3MHz. The LTC3307A operates in forced continuous mode when syncing to an external clock. The DC2990A is set to a fixed 2MHz frequency by connecting RT to V_IN through a 0Ω resistor, R9. The frequency can be easily changed by removing R9 and setting an appropriate resistor in the R4 location to obtain the desired frequency. Refer to the LTC3307A data sheet for the proper RT value for a desired switching frequency.

The DC2990A also has an EMI filter to reduce conducted EMI. This EMI filter can be included by applying the input voltage at the V_IN EMI terminal. The EMI performance of the board is shown in the EMI Test Results section. The red lines in the EMI performance graphs illustrate the CISPR25 Class 5 peak limits for the conducted and radiated emission tests.

The LTC3307A data sheet gives a complete description of the device, operation and application information. The data sheet must be read in conjunction with this demo manual. The LTC3307A is assembled in a 2mm × 2mm LQFN package with exposed pads for low thermal resistance. The layout recommendations for low EMI operation and maximum thermal performance are available in the data sheet section Low EMI PCB Layout.

The Efficiency vs Load graph shows the efficiency and the power loss of the circuit with a 3.3V input in Burst Mode operation.

Resources

Documentation

Data Sheets (1)

PDF

3.32 M

LTC3307A: 5V, 3A Synchronous Step-Down Silent Switcher in 2mm x 2mm LQFN Data Sheet (Rev. B)

Reliability Data (1)

PDF

499.22 K

R523 Reliability Data

User Guides (1)

PDF

1.75 M

DC2990A - Demo Manual

Tools & Simulations

LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

LTspice downloads and documentation

Models for the following parts are available in LTspice:

LTC3307A

LTC3307B

LTpowerCAD

LTpowerCAD^® is a power supply design program which selects power stage components, provides detailed power efficiency, shows quick loop Bode plot stability and load transient analysis, and can export to LTspice for simulation.

To open the project file for this circuit:

Step 1: Download and install LTpowerCAD on your computer.

Step 2: Click on the link(s) in the section below to download part-specific project files.

Step 3: If the project file doesn't run, right-click the link and select "Save Target As." Then start the LTpowerCAD tool and open the project file by selecing "Open Project" from the "File" menu.

LTpowerCAD download and documentation

LTpowerCAD Project Files

LTC3307A Project - 3-5Vin to 1.2V/3A, 2MHz

Design tools for the following parts are available in LTpowerCAD:

LTC3307A

LTC3307B

Reference Materials

Rarely Asked Questions (1)

Point-of-Load DC-to-DC Converters Solve Voltage Accuracy, Efficiency, and...

Technical Articles (1)

High Power Density in a Small Form Factor

Analog Dialogue

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.

Quality And Reliability

Symbols and Footprints

Request Product/Process Change Notifications

Save to myAnalog

Support & Discussions

Contact ADI Technical Support »

Ask your question »

Contact ADI Technical Support »

Ask your question »

Sample & Buy

Sample & Buy functionality exists in desktop site

Back

Check Inventory

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

Price Table Help

Evaluation Boards Pricing displayed is based on 1-piece.

Back

Add to cart

Check Inventory

Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.

Save to myAnalog