News and New Products

External power adapter combines USB power with interchangeable ac plugs

By Margery Conner, Technical Editor -- EDN, 8/28/2008

Portable consumer products increasingly rely on the USB port as a dc power port. The ubiquitous port obviates the need for designers to use that annoying external-power-supply “wall wart” to charge a device’s internal battery or directly power the device. Perhaps more important, because the USB port is an international standard, applications need provide only one power connection to satisfy international markets. The 8W PSM08R adapter from Phihong has a micro-USB output connector and is available with four interchangeable clip-adapter plugs for use in virtually any power outlet worldwide, allowing the use of a single power-adapter part number and simplifying a design’s BOM (bill-of-materials) costs.

The double-insulated adapter has an ac-input range of 90 to 264V and an output of 1.6A at 5V dc and provides short-circuit and overvoltage protection. It meets Energy Star IV specification and fully complies with the US Energy Independence and Security Act. The PSM08R sells for $13.06 (10); the adapters are priced separately.