Micrel Inc. introduced the MIC1344, a 3 A power ORing smart switch offered in a small 2 mm × 2 mm QFN package. The MIC1344 targets handheld devices and systems powered from multiple sources such as wall adapters and auxiliary battery power sources. It is also ideal for applications that require a diode OR function between two input power sources. The MIC1344 is available in volume quantity with 1,000 quantities pricing starting at $2.33.
The device provides a power ORing for two power sources from 2.8 V to 5.5 V. The MIC1344 connects either input A or input B to the output using very low-on resistance power MOSFETs. The power MOSFETs serve as monolithic ORing diodes. The power MOSFETs drop significantly less forward voltage than diodes and help conserve power while increasing voltage headroom which is critical for low voltage battery equipped systems. The key protection features are output-to-input and input-to-input current blocking and built in thermal shutdown. The MIC1344 is fully specified from –40 °C to +125 °C. The device is available in a 12-pin, 2 mm × 2 mm Thin QFN package.