LINEAR High Performance Point-Of-Load DC DC µModule Regulator Vostro 3660 3669 Owner's Manual

10A High Performance Point-of-Load DC/DC µModule Regulator 4.5V to 28V Input, 0.6V to 5V Output in a 15mm × 15mm × 2.8mm Package Design Note 385 Eddie Beville

Introduction LTM4600 to be mounted on the back side of a system

Advancements in board assembly, PCB layout and board, taking advantage of the otherwise unused space. digital IC integration have produced a new generation The µModule regulator switches at a nominal 800k Hz in of densely populated, high performance systems. The a synchronous topology to offer very high efficiency in board-mounted point-of-load (POL) DC/DC power sup- a small form factor and low profile.

plies in these systems are subject to the same demand-

The µModule regulator is offered in two versions. The

ing size, high power and performance requirements as

LTM4600EV operates from an input supply range of 4.5V

other subsystems. The rigorous new POL demands are

to 20V; the LTM4600HVEV operates from 4.5V to 28V.

difficult to meet with traditional controller or regulator

Both offer adjustable output voltages from 0.6V to 5V

ICs, or power modules.

and output currents of 14A peak and 10A continuous. For such demanding applications, an ideal POL power Fault protection features include overvoltage protection supply must meet high performance specifications while and overcurrent protection.

simplifying board assembly—mounting similar to other

Quick and Easy Design

surface mount ICs on the board without requiring special

Figure 2 shows a typical LTM4600EV design for a 2.5V

tooling. Such POL DC/DC regulators must also demon-

output and Figure 3 shows the efficiency of the circuit.

strate exceptional thermal performance with innovative

Although bulk capacitors on the input and output suffice

packaging technology. Power density increases without

in most applications, this design uses two low ESR 10µF

the danger of overheating and shortened device life. The

25V ceramic capacitors to reduce input RMS ripple. The

LTM®4600 µModule® regulator does all of these things.

output voltage is set with an external resistor from the

10A DC/DC µModule Regulator in IC Form Factor VOSET pin to ground. The output capacitors are selected

The LTM4600 µModule regulator is a complete power for low ESR to maintain an initial voltage droop of the supply point-of-load DC/DC regulator with a low profile IC output voltage to approximately ΔVOUT = ILOADSTEP • form-factor. The controller, onboard inductor, MOSFETs RESR in a transient step.

and compensation circuitry are all housed in a 15mm ×

L, LT, LTC, LTM, Linear Technology, µModule and the Linear logo are registered 15mm × 2.8mm LGA surface mount package which weighs trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

only 1.73g (Figure 1). These size parameters allow the

Figure 1. The LTM4600 Offers Unprecedented Power Density in a Small Package