The modules allow low-voltage, high-current CPUs, GPUs, ASICs and DDR memory to be powered from a 48V distribution bus. The company says this enables unprecedented power density, conversion efficiency and low power system distribution loss.

The modules’ introduction follows the Open Compute Project (OCP) Summit 2016, where Google announced its initiative to promote 48V server and distribution infrastructure as a standard for data centres to pioneer ‘green’ data centres. Patrizio Vinciarelli, President and CEO of Vicor, commented: “By promoting an open 48V rack standard, Google is now enabling a reduction in the global cloud electricity footprint.”

Efficient, dense, cost-effective and reliable power distribution is a critical element in data centres and other distributed electronics applications, such as autonomous driving vehicles and LED lighting. A higher distribution bus voltage mean smaller cables and bus bars, lower distribution losses and smaller storage capacitors. Conventional power conversion approaches have not been able to efficiently, or compactly, transform power from a 48V bus into the low voltages (e.g. 3.3, 1.8 and 0.8V) and high currents (e.g. 95A) required by contemporary CPUs or GPUs. Providing efficiencies from a 48V bus that are better than 12V legacy solutions, in a fraction of the space, these modules enable system designers to implement green distributed systems, with high conversion efficiency, high power density and low distribution loss.

The modules include the Cool-Power PI3751-02 buck-boost, pre-regulator module (PRM) and the VTM48Kp020x current multiplier module (VTM). The PRM receives its input from a 48V distributed bus (Vin up to 55V) and drives a controlled factorised bus voltage to the VTM. The VTM generates an output voltage that is 1/24th of the voltage at its input while multiplying by 24X the current delivered to the CPU. In applications that require telemetry and digital control (e.g. CPU, GPU, ASIC and DDR4 memory applications) the company’s PI3020 Digital Control and Telemetry device may be used with a VTM/PRM pair.

Using a MHz ZVS buck-boost topology in a 10 x 14mm LGA package, the PRM delivers up to 240W at 98% efficiency. The VTM’s MHz ZVS/ZCS sine amplitude converter (SAC) delivers up to 95A of continuous current, and up to 190A of peak current, at 95% peak efficiency in a moulded 13 x 23mm ChiP package with greater than 400A/in² current density.

The VTM features very low output impedance, allowing users to remove bulk capacitors from the PoL. Furthermore, only the high current VTM needs to be close to the CPU; the PRM can be located remotely. Unlike conventional buck regulator solutions which require enough phases to handle the full transient current demanded by a CPU operating in ‘turbo’ or ‘boost’ mode, the VTM’s Turbo Mode delivers up to twice its rated continuous current for up to 10ms, to accommodate transient CPU operating modes without sacrificing system power density and cost says the company.