Customers are pushing for increasing power per board and implementing ever more silicon on the PCB with the result that increasing processing density in high-end server designs will continue to have an impact on future power systems. The power demand per board in ICT data servers has increased from 300 W in the early 1980s to more than 1kW today – and it is anticipated that power of 3‑5 kW per board will be required by 2020. Current DC/DC power converter solutions and technologies are not adequate at these power levels.
Today, a 1kW DC/DC converter in a quarter-brick format is a reality with power density figures that could not even be imagined a few years back. Could a 1kW eighth-brick be possible in the near future with advanced packaging and highly integrated components?
This article takes a look at where the power industry is going in terms of component integration, thermal management and more than doubling DC/DC power converter density compared with current state‑of‑the‑art technology.
Today’s DC/DC power converter bricks are still dominated by planar two-dimensional PCB constructions, but customer applications requiring smaller footprints, lower profile devices and reduced parasitic impedances are driving technology for high-density 3D packaging.
The use of 3D packaging technology is limited in these high power bricks, but there are promising developments in embedding both active and passive components, and PCB vendors see this as a major opportunity to move up the value chain. This will include chip stacking, package stacking and component embedding through over-molding. Very important in this area is the integration of magnetic materials with the ultimate solution being integration of the magnetic component on the semiconductor wafer.
The most common technique in 3D packaging is that of embedding components (both active and passive) within the PCB. Embedding of components in the PCB construction offers the power designer significant gains in footprint reduction, enhanced cooling possibilities and, for