Maxim targets systems with a 12V backplane and hot-swap requirements with the new DS4560 hot-plug switch. Applications include enterprise disk drives that must hot plug into a backplanes, and boards in servers and telecom systems. The IC integrates a 25-mΩ n-channel power MOSFET eliminating the need for external components.
The DS4560 powers a load from a 9V to 13.2V sources and delivers as much as 4A of continuous current. The IC integrates a closed-loop controller for the MOSFET to ensure that an configurable current limit isn't exceeded when a board or module is inserted to a backplane and power is applied. The device also clamps the output voltage to protect the load from input-overvoltage stresses. The IC integrates a programmable power-up timer to control power application to the load.
The DS4560 also includes a temperature sensor with hysteresis. Two different versions of the IC can react to excessive temperature in different ways. The DS4560-LO (Latch Off) shuts down and awaits a power-on reset. The DS4560-AR (Auto-Retry) restarts after the device cools to an acceptable level. The ICs cost $0.95 (10,000). Check the data sheet for more details.