The LM5050-2 High Side OR-ing FET Controller operates in conjunction with an external MOSFET as an ideal diode rectifier when connected in series with a power source. This OR-ing controller allows MOSFETs to replace diode rectifiers in power distribution networks thus reducing both power loss and voltage drops. The LM5050-2 controller provides charge pump gate drive for an external N-Channel MOSFET and a fast response comparator to turn off the FET when current flows in the reverse direction. The LM5050-2 can connect power supplies ranging from +6V to +75V and can withstand transients up to +100V. The LM5050-2 also provides a FET test diagnostic mode which allows the system controller to test for shorted MOSFETs.