The switch provides a power ORing for two power sources from 2.8 to 5.5V. Using very low-on resistance power MOSFETs which serve as monolithic ORing diodes, the MIC1344 connects either input A or input B to the output.
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. Key protection features include output-to-input and input-to-input current blocking, and built in thermal shutdown. Fully specified from -40 to +125°C, is available now, priced from $2.33 and sold in 1,000-piece quantities.
“The MIC1344 power ORing switch is designed to reduce heat by minimising voltage drop across the power switch. It saves valuable board space which remains crucial in the design of mobile devices,” said Brian Hedayati, Vice President, Marketing for High Performance Linear and Power Solutions, Micrel. “To increase design flexibility the device also offers programmable current-limit for each channel, automatic or manual input selection and four status outputs.”