DESIGN FEATURES Hot Swap Controller with
Power-Up Timeout Function
Simplifies Hot Swapping Boards
with Multiple Power Supplies
by Anthony Ng and YK Sim Introduction
The LTC4212 is a Hot Swap controller that allows safe board insertion
and removal from a live backplane.
It features a supply range of 2.5V to
16.5V, programmable soft-start with
inrush current limiting, automatic retry or latched mode operation, a high
side drive for an external N-channel
MOSFET and dual level overcurrent
fault protection.
Unlike many Hot Swap controllers,
the LTC4212 does not monitor the load
side of the MOSFET directly. Instead,
the LTC4212 interfaces with external
power supply monitor ICs or directly
with the PGOOD pin of a switching
regulator. This permits the LTC4212 to
monitor any number of supplies on the
board. It has a power-up timeout function that disconnects a card from the
backplane supply when the monitored …