Linear Technology has introduced the LTM4643 quad output step-down µModule (power module) regulator, configurable as a single output (12A), dual (6A and 6A or 9A and 3A), or quad (3A each) regulator in a 9mm x 15mm x 1.82mm ultrathin LGA package. This flexibility enables system designers to rely on one simple and compact regulator for a variety of voltage and load current requirements in FPGA, GPU, ASIC and processor-based applications. The 1.82mm height package allows the device to be mounted on the rear of the PCB, freeing space on the topside for components such as memory and connectors. The device is suitable for systems with height restrictions, such as rear PCB assembly in PCIe applications and where the regulator must fit under a common heat sink or cold plate to cool high power FPGAs, GPUs, ASICs and processors in applications such as embedded computing, data storage, medical imaging and industrial systems. It only requires eight external ceramic capacitors and four feedback resistors to regulate four independently adjustable outputs between 0.6V to 3.3V. Separate input pins enable powering of the four channels from different or a common supply rail(s) from 4V to 20V. The four channels are switched 90 degree out-of-phase to minimise input ripple at the 1.2MHz default switching frequency or synchronised to an external clock between 850kHz and 1.5MHz. With the addition of an external bias supply above 4V, the device can regulate from an input supply voltage as low as 2.375V. Output overvoltage, overcurrent and overtemperature fault protection are included in the regulator. The regulator is available with operation specified over the –40C to 125C internal temperature range.