APPLICATIONS • -48V Hot Swap Power Backplane/Distribution Central Office, Ethernet for VOIP • Positive Voltage Hotswap 12V to 60V Applications (low side switching) • Card Insertion Detection • IP Phone Applications • Databus Power Interfacing • Custom Industrial Power Backplanes • Distributed Power Systems DESCRIPTION The X80070 is a hot swap controller that allows a board to be safely inserted and removed from a live backplane without turning off the main power supply. During insertion, the gate of an external power MOSFET is clamped low to suppress contact bounce. The undervoltage/overvoltage circuits and the power-on reset circuitry suppress the gate turn on until the mechanical bounce has ended. The X80070 turns on the gate with a slew rate to limit the inrush current and incorporates an electronic circuit breaker set by a sense resistor. After the load is successfully charged, the PWRGD signal is asserted; indicating that the device is ready to power sequence the DC-DC power bricks. At all times, the X80070 monitors for undervoltage, overvoltage, and overcurrent conditions. If any fault occurs, the gate will be immediately shut off and the PWRGD will be returned to the inactive state. The X80070 contains overvoltage, undervoltage and overcurrent detection, hardshort retry, gate control slew rate and power good control.