QPT unveils qMicroModule IBC for 800V data centres
UK power electronics innovator QPT has unveiled the qMicroModule IBC, an intermediate bus converter for next-gen AI data centres that in a single step converts 800V DC power to 6V to feed processors' voltage regulators.
It runs on proven 650V GaN, and is built for scaling to higher voltage parts, including 1200V GaN, as they mature and prove suitable.
QPT is opening the design (which delivers up to five times the power density of the converters used today) to semiconductor and power-system partners to license into their own products.
“The whole industry agrees the AI rack is moving to 800 volts. The real question is how you convert that power without giving up the space the processors need,” said James Cannings, CEO of QPT. “We've found a genuinely different way to do it, and we're excited to work with partners on next-generation designs that can make a real difference to one of the fastest-growing needs in AI.”
QPT says it has designed the qMicroModule IBC to allow more rack space to go to processors rather than to power conversion. In addition it scales with the next chip generations: power density rises with switching frequency. Today's resonant designs typically run at around 1 MHz, and gain little by pushing much higher, because their transformer losses climb steeply with frequency. QPT's hard-switched approach keeps scaling into the multi-MHz range, so more power comes from raising the frequency rather than from redesigning or adding converters in parallel.
System cost is also lowered because the converter is designed to react to a sudden change in load within a single switching cycle, which sharply reduces the bulk capacitance power systems carry today to ride out rapid AI load swings. The saving outweighs the modest cost of the control electronics.
Another feature is built-in protection (the same cycle-by-cycle control is designed to shut the converter down within a single switching cycle if a fault occurs).
Hard switching at very high frequency has long been considered impractical, because the switching losses climb as the frequency rises. QPT overcomes this with a combination of its own technologies working together: ZEST, a specialised transformer that stays efficient at very high frequencies; an energy-harvesting network that recovers most of the energy fast switching would otherwise waste; and a control system fast enough to adjust the converter on every switching cycle. No single piece is enough on its own. It is the combination that keeps the losses low as the frequency climbs, and that combination is unique to QPT.
The architecture is not tied to any one device. Two smaller modules are stacked so they share the 800V between them, each handling 400V, which keeps the design comfortably within the rating of proven 650V GaN available today, while leaving it free to adopt higherVage parts as they mature. Their outputs are combined to deliver roughly 5 kW from a compact two-module stack. QPT already runs this high-frequency GaN approach at 1 MHz in its MicroDyno motor drive, around 100 times the frequency of a conventional drive, using the same high-frequency switching and control approach the qMicroModule IBC brings to data-centre power.
There is headroom well beyond this first design, according to the company. QPT's qAttach die-attach moves heat far more effectively than the packaging used across the industry today, giving the same devices room to run at much higher power in later generations.
“Resonant converters run into a wall as you push them to higher frequencies and higher power. Ours keeps scaling: double the switching frequency and you roughly double the power density, with no redesign,” said Rob Gwynne, co-founder and CTO of QPT. “That is the kind of scaling the next GPU generations will need, and it only works because we solve the transformer and the switching losses together.”
QPT is opening a small number of lead design partnerships to semiconductor and power-system companies. For semiconductor makers, it is a differentiated, high-value application for their GaN devices; for power-system designers, a route to leading power density without a redesign for every new processor generation.
The company says it is already in discussions with leading companies in the sector.
