Linear Technology has introduced the LTM4636-1, a 40A to 240A scalable step-down µModule switching regulator. The part incorporates protection circuitry that trips a circuit breaker in the event of overvoltage or overtemperature fault conditions to protect itself, the PCB and loads such as high current low voltage processors, FPGAs, GPUs and ASICs. An output crowbar function quickly clamps the output to protect the load during an overvoltage condition.

The LTM4636-1 benefits from a BGA package construction in which the inductor is exposed on top and is used as a heat sink, permitting direct contact with airflow from any direction for more effective cooling.

Cool in, heat out

By stacking the inductor on top of a 16mm x 16mm BGA package, the LTM4636-1 can deliver 40W with only 40°C rise over the ambient temperature (12VIN, 1VOUT, 40A, 200LFM). Full-power 40W is delivered up to 83°C ambient and half-power 20W is supported at 110°C ambient. In addition to dissipating heat from the top, the LTM4636-1 is designed to uniformly disperse heat from the bottom of the package to the PCB with 144 BGA solder balls, with banks of solder balls assigned as GND, VIN and VOUT where high current flows.

linear tech LTM4636-1 regulator (cr) Figure 1: 40A µModule Regulator with overvoltage and overtemperature protection.  

The LTM4636-1 operates at 92%, 90% and 88% efficiency, delivering 15A, 30A and 40A, respectively, to a 1V load from 12VIN. The µModule regulator is scalable, so four LTM4636-1s in parallel can deliver 160W with only 40°C rise and 88% efficiency (12VIN, 1VOUT, 200LFM).

Total device height is 7.07mm with a 16mm x 16mm BGA footprint. The LTM4636-1 µModule regulator provides DC/DC conversion efficiency, heat dispersion and safety circuitry, ensuring thermal performance, as well as voltage and thermal protection in a small package. The LTM4636-1 operates from 4.7V to 15V input supply and regulates an output voltage from 0.6V to 3.3V. Total DC output voltage accuracy is ±1.3% from –40°C to 125°C.