48V Hot-Swap Controller Immune To Input-Voltage Steps

Allowing telecommunications boards to be safely inserted or removed from a live backplane without damaging the connectors or glitching the power supply, the LT4250 -48V controller protects the board from input-voltage steps and current spikes. It controls and external n-channel MOSFET in the -48V power path and limits inrush current as the bulk capacitance on the board charges up. A sense resistor is employed to program the current limit for the circuit breaker and the controller will limit the current to the programmed level until a fixed time period expires. Programmable under- and over-voltage levels allow users to set the operating voltage range for the board and the on/off threshold is Bellcore compliant. Available in eight-pin PDIP and SO-8 packages, prices start at $2.25 each/1,000. LINEAR TECHNOLOGY, CORP., Milpitas, CA. (408) 432-1900.