LT1640L Datasheet | Linear Technology

LT1640L/LT1640H Negative Voltage Hot Swap Controller Features s s s s s s s DESCRIPTION The LT®1640L/LT1640H is an 8-pin, negative voltage Hot Swap TM controller that allows a board to be safely inserted and removed from a live backplane. Inrush current is limited to a programmable value by controlling the gate voltage of an external N-channel pass transistor. The pass transistor is turned off if the input voltage is less than the programmable undervoltage threshold or greater than the overvoltage threshold. A programmable electronic circuit breaker protects the system against shorts. The PWRGD (LTC1640L) or PWRGD (LTC1640H) signal can be used to directly enable a power module. The LT1640L is designed for modules with a low enable input and the LT1640H for modules with a high enable input. The LT1640L/LT1640H is available in 8-pin PDIP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. Allows Safe Board Insertion and Removal from a Live - 48V Backplane Operates from - 10V to - 80V Programmable Inrush Current Programmable Electronic Circuit Breaker Programmable Overvoltage Protection Programmable Undervoltage Lockout Power Good Control Output U APPLICATIONS s s s Central Office Switching - 48V Distributed Power Systems Negative Power Supply Control TYPICAL APPLICATION Input Inrush Current GND R4 562k 1% UV = 37V R5 9.09k 1% R6 10k 1% 8 VDD 3 UV LT1640L 2 OV VEE 4 SENSE 5 C1 33n F 24V GATE 6 R2 10Ω 5% R3 10k 5% C2 3.3n F 100V 2 1 C3 0.1µF 100V ON/OFF 9 VOUT+ VIN 8 SENSE + 7 TRIM 6 SENSE - 5 VOUT- VIN- + CONTACT BOUNCE PWRGD 1 OV = 71V DRAIN 7 R1 0.02Ω 5% - 48V Q1 IRF530 5V + C4 100µF 100V 4 + C5 100µF 16V 1640...