Power management chips are a part of every product. This interview takes a look at what technologies are shaping this space.
Andy Gales, VP International Sales at Vicor Corp speaks with Dilin Anand from EFY. Vicor designs, manufactures and markets modular power components as well as complete power systems for verticals including aerospace, defence, enterprise, industrial, telecommunications, and automotive markets.
At what rate has power Density improved during the last few years?
We have been able to increase our power density by 25 per cent every two years. This is not a linear increase, and shows the performance that we have been able to achieve. The new bus converters that were launched have been designed to provide very high power density in a very small package. As a result, we have a very small “ChiP” package that is designed to provide isolation and transformation of the input voltage. The power density that this chip is capable of now is extremely high – we can provide up to 2,750 watts per cubic inch in this new package.
What are the new technologies driving these improvements?
We are essentially using a topology called sine amplitude conversion. This is a technology that has been with us since ten years. The Sine Amplitude Converter (SAC) is a neat topology as it allows you to switch direct current (DC) power and convert it to alternating current (AC) to transform and then rectify it. SAC basically modulates the current through a quasi-resonant transformer circuit. The benefit is that we are not switching square waves of power like in pulse width modulation.
Could you explain how this translates into real world benefits?
Transformers don’t like square waves. Instead they prefer sinusoidal current. By passing sine waves through a transformer, we reduce noise and improve efficiency of the system. The traditional problem is that every time you switch there are losses. The higher the frequency of the transformer, the higher would be the resulting losses. With the sine signal you don’t increase losses even if you increase the frequency and the higher switching frequency allows the size of the magnetic components to be reduced.
Could you elaborate on the advances in your packaging technology?
We call it the “ChiP” packaging technology, which stands for converter-housed-in-package. It allows transforming energy more effectively in our inductors. This time we also put it in a VIA packaging, which is a machined metal cladding that aids in thermal dissipation by providing double sided cooling.
Could you explain how VIA packaging compares to alternate solutions that were traditionally used?
VIA packaging provides improved converter thermal performance by removing heat from both the top and bottom of the internal ChiP converter that it houses. This results in improved performance at high ambient temperature.
What are the various ways through which tools have been updated to improve the productivity of the engineers using it?
Power System Designer is a tool on our website www.vicorpower.com, which takes the development stage further by asking VICOR to recommend the components you need to use to solve your particular problems. It will come back and recommend a best-fit solution. It will recommend solutions for best overall, most efficient, lower cost, smallest physical solution. So we can provide information to the designer to what design fits his requirement and then he can simulate and see it too.
Any technology shifts or trends being driven by the market?
The switch to higher voltage bus voltage bus distribution is an enabling technology that will improve systems in the wider market. The trend to move to 48v and even 300v is good. We see a proliferation of higher voltage distribution in systems, which will increase efficiency and reduce conversion stages in systems.
What is enabling the reduction in product size year after year?
Increasing the frequency that power products switch at helps Vicor to reduce the size of the power converter product every few years. It also improves the efficiency of the product. Another point is that power supply can be integrated into the system board now. The option now is to integrate the AC power supply right into the motherboard of the system. This could dramatically change the face of how products are designed and packaged.
What trends do you foresee for the coming years?
We see a trend towards higher distribution voltages within systems as processors continue to increase their power requirements, 12V buses moving to 48V and 48V buses moving to 380V to reduce losses in power distribution. We also see a trend towards more efficient power system architectures by eliminating power conversion stages, driving low voltage processors or ASICs via a single conversion stage directly from a 48V bus rather than converting 48V to 12V and then converting 12V to the load.