Low voltage in & out regulator pushes 20A from micro package

December 05, 2014 // By Graham Prophet
This 20A step-down µModule regulator is optimised for low VIN to low VOUT conversion and delivers 88% efficiency with a 37°C temperature rise

LTM4639 is a 20A DC/DC step-down µModule (micromodule) regulator capable of converting 2.5V to 7V main-power system rails to point-of-load voltages as low as 0.6V with peak efficiency. The LTM4639 is a complete switching point-of-load power supply and includes the inductor, MOSFETs, DC/DC controller and compensation circuitry. It is housed in a 4.92 mm height BGA package with a 15 x 15mm footprint. For 3.3V input to 1.5V output conversion at 20A load, efficiency is 88%, power loss is 3.9W, and junction temperature rise above ambient temperature is 37°C. The micromodule regulator provides a precise output voltage regulation: total DC error of maximum ±1.5%, guaranteed from -40°C to 125°C. Up to four devices can be paralleled for up to 80A output while operating out-of-phase to reduce the number of input and output capacitors.

The LTM4639's input supply range is 2.375V to 7V. For operation from 3.3V and lower, a 5V low power auxiliary supply is needed to bias internal circuitry. Output voltage ranges from 0.6V to 5.5V, with protection functions for overcurrent and overvoltage conditions.

The LTM4639 is rated for operation from -40°C to 125°C and costs $19.45 (1,000)

Linear Technology; www.linear.com/product/LTM4639