LT4180

1

4180fp

Electrical Specifications Subject to Change

TYPICAL APPLICATION

FEATURES

DESCRIPTION

Virtual Remote Sense

Controller

regulation over long, highly resistive cables without

requiring an additional pair of remote sense wires. This

Virtual Remote Sense™ device continuously interrogates

the line impedance and corrects the power supply output

voltage via its feedback loop to maintain a steady voltage

at the load regardless of current changes.

The LT4180 is a full-featured controller with 5mA opto-

isolator sink capability, under/overvoltage lockout,

soft-start and a ±1% internal voltage reference. The

Virtual Remote Sense feature set includes user-program-

mable dither frequency and optional spread spectrum

dither.

The LT4180 works with any topology and type of isolated

or nonisolated power supply, including DC/DC converters

and adjustable linear regulators.

The LT4180 is available in a 24-pin, SSOP package.

Isolated Power Supply with Virtual Remote Sense

APPLICATIONS

n

Tight Load Regulation with Highly Resistive Cables

without Requiring Remote Sense Wiring

n

Compatible with Isolated and Nonisolated Power

Supplies

n

±1% Internal Voltage Reference

n

5mA Sink Current Capability

n

Soft-Correct Reduces Turn-On Transients

n

Undervoltage and Overvoltage Protection

n

Pin-Programmable Dither Frequency

n

Optional Spread Spectrum Dither

n

n

24-Pin SSOP Package

n

12V High Intensity Lamps

n

28V Industrial Systems

n

High Power (>40 Watts) CAT5 Cable Systems

n

Wiring Drop Cancellation for Notebook Computer

Battery Charging

n

AC and DC Adaptors

n

Well-Logging and Other Remote Instrumentation

n

Surveillance Equipment

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

Virtual Remote Sense is a trademark of Linear Technology Corporation. All other trademarks

are the property of their respective owners.

CAT5E CABLE

LINE

LINE

OV

FB

DIV0 DIV1

COMP

DRAIN

SENSE

DIV2 SPREAD CHOLD1 CHOLD2 CHOLD3 CHOLD4

4180 TA01a

RUN

SWITCHING

REGULATOR

+

–

LT4180

VIRTUAL REMOTE SENSE

0

4.97

4.98

4.99

4.96

4.95

0.5

1.5

1

2

2.5

3

4.92

4.91

4.94

5.00

4.93

4180 TAO1b