LT1641-2 Datasheet

• Allows Safe Board Insertion and Removal from a Live Backplane
• Controls Supply Voltage from 9V to 80V
• Programmable Analog Foldback Current Limiting
• High Side Drive for an External N-Channel
• Automatic Retry (LT1641-2)
• User Programmable Supply Voltage Power-Up Rate
• Undervoltage Lockout
• Overvoltage Protection
• Both are available in 8-Lead SO Package

• Hot Board Insertion
• Electronic Circuit Breaker
• Industrial High Side Switch/Circuit Breaker
• 24V/48V Industrial/Alarm Systems

The 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 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 LT1641-2 are available in the 8-lead SO package.