The MAX16126/MAX16127 load-dump/reverse-voltage protection circuits protect power supplies from damaging input voltage conditions, including overvoltage, reverse-voltage, and high-voltage transient pulses. Using a built-in charge pump, the devices control two external back-to-back n-channel MOSFETs that turn off and isolate downstream power supplies during damaging input conditions, such as an automotive load-dump pulse or a reverse-battery condition. Operation is guaranteed down to 3V to ensure proper operation during automotive cold-crank conditions. These devices feature a flag output (active-low FLAG) that asserts during fault conditions.

For reverse-voltage protection, external back-to-back MOSFETs outperform the traditional reverse-battery diode, minimizing the voltage drop and power dissipation during normal operation.