Board-fit and integration for -48V backplane protection
The LTC4251BCS6-1#TRMPBF is a single-channel Hot Swap Controller designed for -48V telecom and datacom backplane environments. It manages inrush current and provides fault protection during board insertion, with the external pass MOSFET handling the load current — the controller itself draws only 800 µA from the supply. The supply voltage range spans -72V to -36V, covering the full -48V nominal rail including transient excursions. Programmable features include circuit breaker threshold, current limit, fault timeout, overvoltage protection (OVP), and undervoltage lockout (UVLO), all set with external resistors and capacitors. Housed in a TSOT-23-6 package (1.6 mm × 2.9 mm body), the controller fits into tight board layouts typical of line-card edge designs.
Active lifecycle and compliance posture
No stock-holding claim is made here — each procurement is verified per request.
Peer comparison — selecting between LTC4251 variants
The closest sibling is the LTC4251BCS6-2#TRMPBF, which shares the same package, supply range, programmable features, and latched-fault response. The functional difference between the -1 and -2 suffixes is the fault-timer timing and current-limit accuracy — the -1 variant uses a shorter fault timeout and tighter current-limit tolerance, making it the preferred choice for applications where fast fault response is critical, such as protecting sensitive line-card loads. If the board sees outdoor or unheated environments, that variant is the direct swap; the commercial-grade -1 part stays in the controlled rack.