LTC3890-1

RECOMMENDED FOR NEW DESIGNS

60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller

Data Sheet Product Selection Table
Viewing:

Overview

  • Wide VIN Range: 4V to 60V (65V Abs Max)
  • Low Operating IQ: 50μA (One Channel On)
  • Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 24V
  • RSENSE or DCR Current Sensing
  • Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
  • Phase-Lockable Frequency (75kHz to 850kHz)
  • Programmable Fixed Frequency (50kHz to 900kHz)
  • Selectable Continuous, Pulse-Skipping or Low Ripple Burst Mode® Operation at Light Loads
  • Very Low Dropout Operation: 99% Duty Cycle
  • Adjustable Output Voltage Soft-Start or Tracking
  • Power Good Output Voltage Monitor
  • Output Overvoltage Protection
  • Low Shutdown IQ: <14μA
  • Internal LDO Powers Gate Drive from VIN or EXTVCC
  • No Current Foldback During Start-Up
  • Narrow SSOP Package

The LTC3890-1 is a high performance dual step-down switching regulator DC/DC controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. Power loss and supply noise are minimized by operating the two controller output stages out-of-phase.

The 50μA no-load quiescent current extends operating life in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. A wide 4V to 60V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries.

Independent TRACK/SS pins for each controller ramp the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous conduction mode at light loads.

For a leadless 32-pin QFN package with additional features of adjustable current limit, clock out, phase modulation and two PGOOD outputs, see the LTC3890 data sheet.


 LTC3890 LTC3890-1 LTC3890-2 LTC3890-3
Adjustable Current Limit Limit Yes No Yes No
CLKOUT/PHASMD for
Multiphase Operation		 Yes No Yes No
Number of PGood
Outputs
2		 1 2 1
OVP – Bottom Gate
Crowbar		 Yes Yes No No
Current Limit Foldback Yes Yes No No
Light Load Operation
when Synced to External
Clock		 Forced Continuous Forced Continuous Pulse Skipping Pulse Skipping
SENSE Pins Common
Mode Range		 Common Mode < 0.5V
Requires VFB < 0.65V		 Common Mode < 0.5V
Requires VFB < 0.65V		 Not Dependant on
VFB. Easy to make a
non-synchronous
Boost or SEPIC		 Not Dependant on
VFB. Easy to make a
non-synchronous
Boost or SEPIC
Package 5 × 5 QFN-32 SSOP-28 5 × 5 QFN-32 SSOP-28

Applications

  • Automotive Always-On Systems
  • Battery Operated Digital Devices
  • Distributed DC Power Systems
LTC3890-1
60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller
High Efficiency Dual 8.5V/3.3V Output Step-Down Converter Efficiency and Power Loss vs Output Current Product Package 1
Add to myAnalog

Add product to the Products section of myAnalog (to receive notifications), to an existing project or to a new project.

Create New Project
Ask a Question

Documentation

Data Sheet 1

Reliability Data 1

User Guide 2

Data Sheet

This is the most up-to-date revision of the Data Sheet.

Learn More
Add to myAnalog

Add media to the Resources section of myAnalog, to an existing project or to a new project.

Create New Project

Software Resources

Can't find the software or driver you need?

Request a Driver/Software

Hardware Ecosystem

Parts Product Life Cycle Description
Circuit Monitors 1
LTC2960
RECOMMENDED FOR NEW DESIGNS 36V Nano-Current Two-Input Voltage Monitor
Power System Management (PSM) & Sequencers 1
LTC2974
RECOMMENDED FOR NEW DESIGNS 4-Channel PMBus Power System Manager Featuring Accurate Output Current Measurement
Protection Switches & Controllers 1
LT4363
RECOMMENDED FOR NEW DESIGNS High Voltage Surge Stopper with Current Limit
Switching Regulators & Controllers 1
LTC3880
RECOMMENDED FOR NEW DESIGNS Dual Output PolyPhase Step-Down DC/DC Controller with Digital Power System Management
Modal heading
Add to myAnalog

Add product to the Products section of myAnalog (to receive notifications), to an existing project or to a new project.

Create New Project

Tools & Simulations

LTspice 1

Models for the following parts are available in LTspice:

  • LTC3890
  • LTC3890-1
  • LTC3890-2
  • LTC3890-3

LTpowerCAD 2

Design tools for the following parts are available in LTpowerCAD:

  • LTC3890
  • LTC3890-2
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.

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.

Evaluation Kits

eval board
schematic 1
DC1244A

LTC3890EGN-1 Demo Board | 4.5V ≤ VIN ≤ 60V, VOUT1 = 3.3V @ 5A, VOUT2 = 8.5V @ 3A

Buy Now View Details

Product Details

Demonstration circuit 1244 is a Low Quiescent Current, Dual Output Synchronous Buck Converter featuring the LTC3890EGN-1. DC1244 converts a 4.5V to 60V voltage source to 3.3V at 5.0A and 8.5V at 3.0A. When the input voltage is close to or below 9V, the 8.5V output enters dropout mode.The "-1" version has a fixed current limit and current foldback. See data sheet for other differences.


 


eval board
schematic 2
DC2299A-B

LTC3890EGN-1 Demo Board | 6V ≤ VIN ≤ 60V; VOUT1 = 5V @ 8A, VOUT2 = 12V @ 5A

Buy Now View Details

Product Details

Demonstration circuit 2299A is a high input voltage, high efficiency synchronous dual output buck converter featuring the LTC3890EGN. The DC2299A has a wide input voltage range of 6V to 60V. The output voltages are set to 5V and 12V, however, the output voltage can go as high as 24V, with certain modifications. This demo board is capable of delivering up to 8A from the 5V output and up to 5A from the 12V output.
DC1244A
LTC3890EGN-1 Demo Board | 4.5V ≤ VIN ≤ 60V, VOUT1 = 3.3V @ 5A, VOUT2 = 8.5V @ 3A
DC1244A - Schematic
DC2299A-B
LTC3890EGN-1 Demo Board | 6V ≤ VIN ≤ 60V; VOUT1 = 5V @ 8A, VOUT2 = 12V @ 5A
DC2299A - Schematic

Latest Discussions

No discussions on LTC3890-1 yet. Have something to say?

Start a Discussion on EngineerZone®

Recently Viewed