Regulator module provides dual 10A or single 20A outputs for FPGAs, GPUs and ASICs

February 05, 2018 // By Nick Flaherty
Analog Devices has launched a step-down µModule point-of-load regulator with dual 10A or single 20A outputs from 5V or 12V input supply rails.

The LTM4646 includes the inductors, MOSFETs, a DC-DC controller and supporting components, and is housed in a 11.25mm x 15mm x 5.01mm BGA package.

Compared to the previous 2 x single 10A output module, the LTM4646 reduces the solution size of more than 25% and meets the PCB area constraints of densely populated system boards to power low voltage and high current devices such as FPGAs, ASICs, microprocessors and GPUs. Applications include PCIe boards, communication infrastructure, cloud computing-based systems, as well as medical, industrial, and test and measurement equipment.

The accuracy of the total output DC voltage is guaranteed at ±1.5% over line, load and temperature (–40°C to 125°C) and the onboard remote sense amplifiers on both outputs compensate for voltage drop caused by trace impedance of the PC board due to large load currents. The module has selectable internal or external feedback loop compensation, enabling users to optimize loop stability and transient performance while minimizing the number of output capacitors.

The peak efficiency at 12V IN to 1.0V OUT is 86%. With a 200LFM air flow, the LTM4646 delivers a full 20A continuously up to 85°C ambient and the current mode architecture allows multiphase parallel operation to increase output current with very good current sharing.

Standalone, the LTM4646 operates from 4.5V to 20V input range. When 5V external bias is available, the device can operate from 2.375V. The output voltages are adjustable from 0.6V to 5.5V, enabling the device to generate not only low voltage for digital devices but also 2.5V, 3.3V and 5V, which are commonly needed in system bus voltages. The switching frequency can be programmed from 250kHz to 1.3MHz with one resistor, and can also be synchronized to an external clock ranging from 300kHz to 1MHz for noise-sensitive applications. Additionally, it features overvoltage and overcurrent protection.

The LTM4646 operates from –40°C to 125°C with SAC305 (RoHS) and SnPb (63/37) BGA ball finishes. The module is available now from $18.85 in quantities