Texas Instruments Inc. (TI, Dallas, TX) introduced a family of ultra-low, RDS(on) power switches that enables seamless transition between two power sources, such as a single-cell, lithium-ion battery and a wall adapter. Suitable for mobile phones, personal digital assistants and other handhelds, the controlled output-voltage transition times of the new devices allow for a seamless supply transition without requiring a large output (hold-up) capacitor.
The new TPS211x family of two-input, one-output, power multiplexers has two internal high-side, power MOSFETs with RDS(on) as low as 84 mOhms typical to 120mOhms typical. The series of devices, which operates from 2.8V to 5.5V and delivers up to 1A, offers a comprehensive set of features and options to simplify design and provide added flexibility. Select devices have manual switching capabilities using the D0 and D1 control lines, as well as an "auto-switching" mode where the switchover is automatically set to the higher input voltage, or determined by a voltage threshold set by an external resistor divider if the device features an adjustable threshold.
The TPS211x family of two-input, one-output, power multiplexers are available now in an eight-pin, thin-shrink, small outline package. Suggested resale pricing for the TPS211x in quantities of 1,000 units is $0.70.
