LTM4656 datasheet(9/28 Pages) AD

9 / 28 page

LTM4656/LTM4656-1

Rev. 0

For more information www.analog.com

OPERATION

The LTM4656 is a single output standalone non-isolated

step-up switching mode DC/DC power supply with input

currentlimitprotectionduringanoutputshort.Thismodule

provides a precisely regulated output voltage program-

mable via one external resistor from 6V to 36V and deliv-

ers up to 5A output current with few external input and

output capacitors. During normal operation the LTM4656

senses input current through an input protected front end.

The LTM4656 softly turns on with a controlled inrush and

will perform a low duty cycle auto-retry during an output

short circuit. The output short trip time is controlled by

how much short-circuit current is applied and the amount

of voltage across the in-line protection switch. The typical

application schematic is shown in Figure 17. See Typical

Applications section for explanation and curves.

The LTM4656 contains an integrated fixed frequency,

current mode boost controller, power MOSFETs, induc-

tor, in-line protect circuitry and other supporting discrete

components. The default switching frequency is 500kHz.

For noise-sensitive applications, the switching frequency

can be adjusted by an external resistor and the µModule

regulator can be externally synchronized to a clock.

With current mode control and internal feedback loop

compensation, the LTM4656 module has sufficient stabil-

ity margins and good transient performance with a wide

range of output capacitors, even with all ceramic output

capacitors.

Current mode control allows the LTM4656 to parallel for

increase power delivery.

LTM4656 Datasheet(PDF) 9 Page - Analog Devices