Hot swap controller with AEC-Q100 grade
The LTC4231HMS-1#WPBF is a single-channel hot swap controller from Analog Devices, part of the Automotive AEC-Q100 series. It manages inrush current and protects against supply faults when a board is inserted live into a backplane or battery bus.
Programmable protection set
Six programmable features are built in: circuit breaker threshold, current limit, fault timeout, overvoltage protection (OVP), slew rate control, and undervoltage lockout (UVLO). This means the controller can be tuned to the specific load capacitance and supply impedance of the target system — no external comparator or timer IC needed. The latched fault behaviour (LTC4231HMS-1 variant) shuts off the external N-channel MOSFET on a fault and holds it off until the supply is cycled or the ON pin is toggled. This is the preferred response for safety-critical rails where an auto-retry could cause repeated stress. No internal switch is provided — the controller drives an external N-channel pass FET. The designer selects the FET based on the load current and SOA requirements, keeping the thermal dissipation off the controller package.
Package and board-fit note
Supplied in a 12-lead TSSOP (3.00 mm width) and also specified as the supplier device package 12-MSOP. The two packages share the same 0.65 mm pitch footprint and are functionally identical — the MSOP is a thinner-body variant of the same leadframe. The 0.118-inch body width fits in tight channel spacing on a multi-rail hot-swap card.