FEATURES
Continuous 3.3V output from three inputs Complete power management solution VCC, VSBY regulator supplies 500mA output Built-in hysteresis when selecting input supplies Drive control signal for external VAUX switch Output can be forced higher than input (off-state) DESCRIPTION
Power is always taken in priority using the following order: VCC, VSBY, and VAUX. When either VCC or VSBY is present, the device automatically enables the regulator and produces a stable 3.3V output. When only VAUX (3.3V) is present, the drive control output will turn on an external P-MOSFET switch from an auxiliary 3.3V supply VAUX to maintain VOUT. The IC also prevents excessive current from flowing back from VOUT to either input or ground when the output voltage is greater than the input voltage. All the control circuitry needed to provide a a smooth and automatic transition between all three supplies has been incorporated. This allows both VCC and VSBY to be dynamically switched without loss of output voltage.
Silicon Standard
