Report From 1st International Workshop On Power Supply on Chip

Tyndall National Institute in Cork, Ireland, recently organized the inaugural International Workshop on Power Supply on Chip (PwrSoc’ 08) in Cork. The workshop organizers described it as a timely and overwhelming success with double the number of expected attendees. More than 120 leading industry and academic players from across the world participated in the workshop. Over 25 companies and 34 research institutes from 16 different countries discussed the most recent results and the technology challenges and market opportunities in this emerging area. Over 40 attendees attended from the US, 20 from Ireland, 55 from Europe with the remainder from China and Japan. Prof. Gerard Hurley, NUI Galway, who organized PESC2000 in Galway was General Chair for the workshop. The workshop program co-chairs were Dr. Cian Ó Mathúna, Tyndall National Institute and Francesco Carobolante of Qualcomm.

Dr. Ó Mathúna explained the rationale behind the workshop, "PwrSoC’08 is the first international workshop to address the issue of the development of next generation, miniaturized switched mode power supply product formats for use in future mobile phones, portable electronics and high performance computing platforms. These multi-component products can be referred to as power supply-in-package (PSiP) and power supply-on-chip (PwrSoC). This concept of integrated power solutions presents a significant disruptive opportunity in power management and warrants an international forum for its discussion and for the elucidation of the key challenges and opportunities that lie ahead."

The workshop included 50 of the leading experts in this emerging field from Europe, the USA, China and Japan. Companies represented included Anagenesis, Enpirion, Fairchild Semiconductors, Infineon, Intel, International Rectifier, National Semiconductor, NXP Semiconductors, ON Semiconductor, Panasonic, Qualcomm, ST Microelectronics, Texas Instruments, TDK and Vicor. Senior US academics from Berkeley, CPES, Dartmouth, MIT, RPI, Stanford and University of Central Florida were also in attendance. European institutes represented included INSA Lyon; CNRS Toulouse; LETI, Grenoble; TU Delft and Universidad Politécnica de Madrid as well as Irish researchers from University College Cork, University of Limerick and Cork Institute of Technology.

The strong attendance from the semiconductor industry confirmed the trend in recent years whereby power supply miniaturization is opening up significant new business opportunities for semiconductor companies through their ability to deliver advanced processing and functional integration in the form of system-in-package (SiP) and system-on-chip (SoC) platforms.

Over two and a half days, the workshop single-track sessions presented a focused, multi-disciplinary forum during which a range of issues were discussed in an open, informal setting. Initially, key target markets and end-user drivers which were presented extended from power delivery for portable electronics to high performance computing. The workshop Keynote presentation was given by CPES Director, Dr. Fred C. Lee, and Ph.D. student, Qiang Li, and presented a comprehensive "Survey of Trends for Integrated Point-of-Load Converters."

One of the anticipated early adopters of PwrSoC technology is the portable electronics market with miniaturized PwrSoC SMPS components presenting a viable alternative to low efficiency linear regulators, thereby enabling considerable energy savings by significantly extending the lifetime of batteries in mobile phones and other portable electronics. In the case of multi-core computing architectures, Intel presented the opportunity that a high current PwrSoC platform could provide in replacing the conventional VRM (voltage regulation module) and enabling local power delivery directly on the microprocessor or in the package.

This setting of the scene was followed by technology sessions on power semiconductors, topologies and control, passive components and packaging. Many of the speakers saw the major challenge to the further miniaturization of dc-dc converters as the inability to integrate the passive components on silicon due to their relatively large size at today’s operating frequencies of 0.5 to 5 MHz. Many presentations discussed the benefit offered by increasing the switching frequencies into the 10 to 100 MHz region thereby enabling the reduction of passive component values to the point where, with the right technology, their size becomes compatible with silicon device dimensions. Dr. Ó Mathúna said, "MultiMHz operation presents the opportunity to allow the bulky magnetic components to be miniaturised to such an extent that they can be integrated with the silicon chip into a PwrSoC component with a footprint as small as 1mm."

The Micropower team at Tyndall presented the most recent results from their research into micromagnetics on silicon for PwrSoC applications. The Tyndall micro-inductor structure consists of a racetrack of electroplated copper windings encased in a thin film, electroplated, closed, nickel-iron soft magnetic core. Dr. Terence O’Donnell presented efficiency data for micro-inductors of more than 90%, operating at 20MHz and delivering 0.5 Amps, within a footprint of 5.5mm. The micro-inductors were demonstrated with a monolithic "MOSFETs and driver" power-train IC, operating in the 15 to 65MHz range, which was designed by project partners, PERL (Power Electronics Research Laboratory) at University College Cork, led by Dr. Ray Foley. Optimisation analysis undertaken by the Tyndall team demonstrates that micro-inductor efficiencies as high as 95% can be achieved in a footprint of 3mm square at 100MHz.

"Tyndall’s patented technology, in this area, is the result of more than 50 person years of research over the last decade, funded by the Irish Government, with specific direction from the Irish power electronics industry" said Dr. Ó Mathúna. Jeff Shepard, Darnell Group President, whose team covered the event, outlined the key value of Tyndall’s technology. "Currently mobile phones use linear regulators to deliver power from the battery to many of the silicon chips – these are very inefficient (less than 50%) and waste a lot of energy. With Tyndall’s novel micromagnetics technology, it will be possible to increase efficiency up to 80 or 90%, significantly extending battery life."

The key feedback from the workshop attendees was the fact that the workshop offered a unique opportunity for the full PwrSoC value chain to congregate and discuss the challenges and opportunities in this emerging product space. A 50:50 representation of the key industry/academic players was of significant value and validated the need for such an international forum at this time. Based on the overwhelming support for the workshop, it is proposed to issue a CD of the workshop presentations and posters and there are plans to organize the event on a bi-annual basis. Darnell’s PowerPulse.net news service was the media sponsor of the Workshop. The event received technical sponsorship from IEEE PELS, PSMA and the European Center for Power Electronics. Financial sponsorship was received from Enterprise Ireland, PEIG (the Irish Power Electronics Industry Group) and MIDAS (the Irish Microelectronics Industry Design Association).