LTC4420IMSE#PBF (LINEAR TECHNOLOGY)

The LTC4420IMSE#PBF is an 18V dual input micropower PowerPath prioritizer with back-up supply monitoring in 12 pin MSOP package. This monolithic PowerPath prioritizer with low operating current provides back-up switchover for keeping critical circuitry alive during brown out and power loss conditions. Unlike diode-OR products, little current is drawn from inactive supply even if its voltage is greater than active supply. Internal dual 2ohm, 0.5A current limited PMOS switches provide power path selection from a primary input (V1) or a backup input (V2) to output. Two adjustable voltage monitors set via external resistive dividers provide flexibility in setting V1 to V2 switchover and V2 undervoltage thresholds. V1 is monitored continuously while V2 supply monitoring includes controllable low duty cycle UV monitoring. When primary input V1 drops, the ADJ monitor causes OUT to be switched to V2. When V2 drops, it is disconnected from OUT if active-low V2DIS is low.