LT3741



3741f

Typical applicaTion

DescripTion

High Power, Constant

Current, Constant Voltage,

Step-Down Controller

DC/DCcontrollerdesignedtoaccuratelyregulatetheoutput

current at up to 20A. The average current-mode controller

willmaintaininductorcurrentregulationoverawideoutput

set by an analog voltage on the CTRL pins and an external

sense resistor. Due to its unique topology, the LT3741 is

capable of sourcing and sinking current. The regulated

voltage and overvoltage protection are set with a voltage

divider from the output to the FB pin. Soft-Start is provided

to allow a gradual increase in the regulated current during

startup. The switching frequency is programmable from

200kHz to 1MHz through an external resistor on the RT

pin or through the use of the SYNC pin and an external

clock signal.

Additional Features include an accurate external reference

voltage for use with the CTRL pins, an accurate UVLO/EN

pin that allows for programmable UVLO hysteresis, and

thermal shutdown.

L

, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear

Technology Corporation. All other trademarks are the property of their respective owners.

Protected by U.S. Patents including 7199560, 7321203 and others pending.

10V/20A Constant Current, Constant Voltage Step-Down Converter

FeaTures

applicaTions

n

Control Pin Provides Accurate Control of Regulated

Output Current

n

1.5% Voltage Regulation Accuracy

n

±6% Current Regulation Accuracy

n

6V to 36V Input Voltage Range

n

n

Average Current Mode Control

n

<1µA Shutdown Current

n

Up to 94% Efficiency

n

Additional Pin for Thermal Control of Load Current

n

Thermally Enhanced 4mm

× 4mm QFN and 20-Pin

FE Package

n

General Purpose Industrial

n

Super-Cap Charging

n

Applications Needing Extreme Short-Circuit

Protection and/or Accurate Output Current Limit

n

Constant Current or Constant Voltage Source

EN/UVLO

EN/UVLO

HG

CBOOT

VC

CTRL1

CTRL2

LT3741

RT

SYNC

SW

LG

GND

220nF

2.2µH

22µF

2.5m

FB

10nF

39.2k

5.6nF

82.5k

88.7k

3741 TA01a

12.1k

150µF

2

10nF

100µF

14V TO 36V

10V

20A

1µF

SS

45.3k

0 2 4 6 8 10 12 14 16 18

6

8

12

10

3741 TA01b

4

2

0

22

20