The LT1641-1/LT1641-2 are 8-pin Hot Swap controllers that allow a board to be safely inserted and removed from a live backplane. Using an external N-channel pass transistor, the board supply voltage can be ramped up at a programmable rate. A high side switch driver controls an N-channel gate for supply voltages ranging from 9V to 80V. The chips feature a programmable analog foldback current limit circuit. If the chips remain in current limit for more than a programmable time, the N-channel pass transistor is either latched off (LT1641-1) or is set to automatically restart after a time-out delay (LT1641-2). The PWRGD output indicates when the output voltage, sensed by the FB pin, is within tolerance. The ON pin provides programmable undervoltage lockout. The LT1641-1/LT1641-2 are available in the 8-lead SO package.
