• 简体中文
• English

LT4256-1 and LT4256-2 - Positive High Voltage Hot Swap Controllers

The LT4256-1/LT4256-2 are high voltage Hot Swap™ controllers that allow a board to be safely inserted and removed from a live backplane. An internal driver drives an external N-channel MOSFET switch to control supply voltages ranging from 10.8V to 80V.

The LT4256-1/LT4256-2 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 and the PWRGD output asserts low. The LT4256-2 automatically restarts after a time-out delay. The LT4256-1 latches off until the UV pin is cycled low.

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

The LT4256 can be used as an upgrade to LT1641 designs. See Table 1 on page 14 for upgraded specifications.

The LT4256-1 and LT4256-2 are available in an 8-pin SO package that is pin compatible with the LT1641.

Features Allows Safe Board Insertion and Removal from a Live Backplane Controls Supply Voltage from 10.8V to 80V Foldback Current Limiting Overcurrent Fault Detection Drives an External N-Channel MOSFET Programmable Supply Voltage Power-Up Rate Undervoltage Protection Latch Off Operation Mode (LT4256-1) Automatic Retry (LT4256-2) Available in an 8-Pin SO Package Typical Application

Applications Hot Board Insertion Electronic Circuit Breaker/Power Bussing Industrial High Side Switch/Circuit Breaker 24V/48V Industrial/Alarm Systems Ideally Suited for 12V, 24V and 48V Distributed Power Systems 48V Telecom Systems Packaging

Order Information

Demo Boards