PORTLAND, Ore. As mobile handsets, media players and pocket cameras continue to shrink in size while simultaneously increasing their features, design engineers are having a difficult time finding space for connectors required for data transfers, batter charging, earplugs or microphones.
Freescale Semiconductor Inc. (Austin, Texas) claims to have solved the problem by multiplexing these functions onto a single USB connector.
Previously, USB connectors at three different sizes could not be serviced by a single, standard chip. After designing custom chips for OEMs that enable multiple uses of USB connectors, Freescale began offering a standard chip to customers who can't afford a custom chip, and who must today cobble together multiple components.
“Today engineers either need to design a custom chip or use discrete components and analog switches,” said Mike Jennings, market segment manager at Freescale. “The advantage of our single-chip solution is that it offers a much smaller footprint, consumes very little power and can support the faster transfer rates of USB 2.x.”
Freescale's MC34825 Mini-USB chip enables a single low-profile USB connector to provide device communications, including data, audio and battery charging. It works with most chargers by adjusting the current supplied to the device. Standby current is 10 microamps, and up to 32 buttons can be detected on a single line, allowing play, pause, fast forward and similar functions to be built into peripherals like headsets.
Freescale said six OEMs are currently designing its Mini-USB chip into devices like mobile phones, media players, navigation devices, cameras and eBooks.