40A µModule regulator enhances thermal conduction for cooler operation

Linear Technology has unveiled a 40A step-down µModule switching regulator with 3D construction for quicker heat dissipation and cooler operation in a small package.

According to the company by stacking its inductor on top of a 16mm x 16mm BGA package the module, the LTM4636, is able to benefit from the exposed inductor as a heat sink, permitting direct contact with airflow from any direction to cool the device. It is able to deliver 40W (12VIN, 1VOUT, 40A, 200LFM) with only 40°C rise over ambient temperature.

Full-power 40W is delivered up to 83°C ambient and half-power 20W is supported at 110°C ambient.

The LTM4636 operates at 92%, 90% and 88% efficiency, delivering 15A, 30A and 40A, respectively, to a 1V load (12VIN). The µModule regulator is scalable, such that four LTM4636s in parallel current sharing mode are able to deliver 160W with only 40°C rise and 88% efficiency (12VIN, 1VOUT, 400LFM).

Device height is 7.07mm, including the inductor stacked on top of a 16mm x 16mm x 1.91mm BGA package.

In addition to dissipating heat from the top, the LTM4636 is designed to uniformly disperse heat from the bottom of the package to the PCB with 144 BGA solder balls, with banks of them assigned to GND, VIN and VOUT where high current flows.

The LTM4636 operates from a 4.7V to 15V input supply and regulates an output voltage from 0.6V to 3.3V. Total DC output voltage accuracy is ±3% from –40°C to 125°C.

Neil Tyler