What this -48V hot swap controller brings to the backplane
The LTC4252BIMS-2#PBF is a single-channel hot swap controller from Analog Devices designed for -48V supply rails, the standard in telecom and networking infrastructure. It manages board insertion into a live backplane by ramping the external N-channel MOSFET gate, limiting inrush current and protecting against overcurrent and overvoltage events. The part integrates programmable current limit, fault timeout, undervoltage lockout (UVLO), and overvoltage protection (OVP), and includes an auto-retry feature that cycles the load after a fault clears — useful for remote or unattended equipment where a manual reset isn't practical.
Active status — no LTB clock ticking
This part carries an Active lifecycle status and is ROHS3 compliant. There is no last-time-buy window or end-of-life notice to watch. For a -48V hot swap controller that's been in production for years, that's a clean signal for both new designs and sustaining production.
Package and environment — 10-MSOP, industrial temp
Housed in a 10-MSOP (3.00 mm width) surface-mount package, the LTC4252BIMS-2#PBF fits compact line cards and mezzanine boards. The operating temperature range of -40°C to 85°C covers most indoor telecom and industrial environments. No internal switch — the controller drives an external N-channel MOSFET, so the thermal dissipation sits off-chip, which simplifies layout for higher-current rails.
Supply current and programmable features
Quiescent supply current is 800 µA, a reasonable budget for a supervisory controller that stays alive on the -48V rail. The programmable feature set — current limit, fault timeout, OVP, and UVLO — gives the board designer control over the insertion profile and fault response without external comparators or timers.