MAX5938

The MAX5938 is a hot-swap controller for -10V to -80V rails. The MAX5938 allows circuit line cards to be safely hot-plugged into a live backplane without causing a glitch on the power supply. It integrates an adjustable circuit-breaker function requiring no RSENSE.

The MAX5938 provides a controlled turn-on for circuit cards, which limits inrush current and prevents both glitches on the power-supply rail and damage to board connectors and components. Before startup, the MAX5938 performs a Load Probe™ test to detect the presence of a short-circuit condition. If a short-circuit condition does not exist, the device limits the inrush current drawn by the load by gradually turning on the external MOSFET. Once the external MOSFET is fully enhanced, the MAX5938 provides overcurrent and shortcircuit protection by monitoring the voltage drop across the RDS(ON) of the external power MOSFET. The MAX5938 integrates a 400mA fast GATE pulldown to guarantee that the external MOSFET is rapidly turned off in the event of an overcurrent or short-circuit condition.

The MAX5938 also protects the system against input voltage (VIN) steps. During an input voltage step, the device limits the current drawn by the load to a safe level without shutting down the load. The device also includes ON/OFF control, selectable PGOOD output polarity, undervoltage (UV) and overvoltage (OV) protection.

The device offers latched (MAX5938L) or autoretry (MAX5938A) fault management. Both the MAX5938A and MAX5938L are available in a 16-pin QSOP package and are specified for the extended (-40°C to +85°C) temperature range.