LT4256-3

Supply Voltage (VCC) ................................  0.3 to 100V
SENSE, PWRGD .......................................  0.3 to 100V
GATE Voltage (Note 2) ....................  0.3V to VCC + 10V
GATE Maximum Current ..................................... 200mA
VOUT .......................................................... 3V to 100V
FB, UV, OPEN ............................................. 0.3 to 44V
OV .............................................................. 0.3 to 18V
RETRY ........................................................ 0.3 to 15V
TIMER Voltage .........................................  0.3V to 4.3V
Maximum Input Current (TIMER) ....................... 100mA
Operating Temperature
LT4256-3C ............................................. 0°C to 70°C
LT4256-3I ......................................... 40°C to 85°C
Storage Temperature Range ................  65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C

The LT®4256-3 is a high voltage Hot SwapTM controller that allows a board to be safely inserted and removed from  live backplane. An internal driver controls the high side N-channel MOSFET gate for supply voltages ranging from 10.8V to 80V. The part features an open-circuit detect (OPEN) output that indicates abnormally low load current conditions.

The LT4256-3 also features an adjustable analog foldback current limit. If the supply remains in current limit for more than a programmable time, the N-channel MOSFET shuts off, the PWRGD output asserts low and the LT4256-3 either automatically restarts after a time-out delay or latches off until the UV pin is cycled low (depending on the status of the RETRY pin).

The PWRGD output indicates when the output voltage rises above a programmed level. An external resistor
string from VCC provides programmable undervoltage and overvoltage protection.

The LT4256-3 is available in a 16-lead SSOP package.  LTC and LT are registered trademarks of Linear Technology Corporation.