Global Designer: Hong Kong team wins power-supply-design contest

Design contests are big things in Asia these days, because there is a feeling that Asian designers lack system-design expertise. Therefore, semiconductor companies, such as On Semiconductor, have started to promote design contests in the region to improve this deficiency. Seen in this light, Asian designers seem to be doing rather well.

Hong Kong Polytechnic University (HKPU, www.polyu.edu.hk) won the Grand Champion and Best in Class A2 awards in the Open Category in the Efficiency Challenge 2004 design competition. On Semiconductor recently bestowed the awards at the APEC (Applied Power Electronics Conference) in Austin, TX. HKPU's Grand Champion winning entry is a power-supply design for an external, stand-alone, AA-battery charger. The university's second entry, an external power supply for a cordless phone, won the Best in Sub-Class B2.

The HKPU team, comprising Martin Chow Hoi-lam, PhD; Professor Lee Yim-shu; Cheng Yiu-lam; and Lee Chung-ping, belong to the Power Electronics Research Centre in the university's Department of Electronic and Information Engineering. The team used On Semiconductor's devices in their award-winning design (Picture).

The Efficiency Challenge contest featured two major categories: the Open Category for power-supply designs without cost constraints and the Market Ready Category for cost-effective power-supply designs in consumer electronics. Companies and universities in the United States, Taiwan, and Hong Kong participated in the contest.

The HKPU team based its AA-battery-charger design on On Semiconductor's NCP1215A variable-off-time switch-mode power-supply controller. The design features 6.25V output voltage, 2.5W output power, and 0.4A output current. The power-supply design delivers an average active-power efficiency of 74% and a no-load power consumption of 0.16W. The judges observed that HKPU's AA-battery charger has an impressively low parts count and that the device delivers good efficiency for such a low output power. They noted also that its no-load power consumption of 0.16W is remarkable.

Applied Power Electronics Conference, http://apec-conf.org.