Mobile phone Circuits to Get Even smaller

Mobile phone Circuits to Get Even smaller

Transceivers, appliances such as mobile phones that can send and receive messages, have become smaller and smaller over the last few years, but users are about to experience a new meaning in miniaturisation. Research at The Hong Kong University of Science & Technology (HKUST) has successfully combined a unique system architecture and new circuit design techniques to reduce them in size like never before.Principal Investigator Dr Howard Luong said the handset of a typical mobile phone today may contain between 150 and 300 separate electrical components.

Transceiver circuitry (left) and Dr Leung’s equivalent combining off-chip components

His research group proposed and demonstrated circuit techniques that make it possible to combine many of these components to a single chip and therefore to significantly reduce the size of circuitry (see example in graphic). A US patent has been granted for one of the circuit techniques. The transformation applies to the CMOS (Complimentary Metal-Oxide Semiconductor) manufacturing process, which can produce integrated circuits and systems with the highest integration level at the lowest cost. Applying new techniques to the CMOS process, Dr Luong’s research enables many “off-chip”components to be combined to realize a system-on-chip. “But,” he said, “this integration created great challenges in circuit implementation.” Part of the research was to solve the problems by new circuit design techniques.“The system architecture and circuitry go hand in hand, he added. “They must both work, or neither will be useful.” The resulting design gives the highest component integration in the smallest chip area ever reported, said Dr Luong.In his design, all off-chip components are fitted into a central chip measuring 36 mm with packaging, and 8mmwithout being packaged. Dr Luong’s miniaturisation method means appliances will soon be made for even lower cost and lower power consumption in addition to being much smaller in size and lighter in weight.“With the lowering of cost, size and power, many new and interesting applications will become possible and practical,” he said. Low-power wireless transceivers, for example, could be integrated into implanted devices such as heart pacemakers to wirelessly transmit and receive information between patients and doctors or monitoring systems. Wearable mobile phones as small as wrist watches at an affordable price could also become a reality.