MAX5949B Datasheet | Maxim Integrated

19-3494; Rev 1; 8/11 MAX5949A/MAX5949B -48V Hot-Swap Controllers with External RSENSE General Description The MAX5949A/MAX5949B are hot-swap controllers that allow a circuit card to be safely hot plugged into a live backplane. The MAX5949A/MAX5949B operate from -20V to -80V and are well-suited for -48V power systems. These devices are pin and function patible with the LT4250 and pin patible with the LT1640. The MAX5949A/MAX5949B provide a controlled turn-on to circuit cards preventing glitches on the power-supply rail and damage to board connectors and ponents. The MAX5949A/MAX5949B provide undervoltage, overvoltage, and overcurrent protection. These devices ensure the input voltage is stable and within tolerance before applying power to the load. Both the MAX5949A and MAX5949B protect a system against overcurrent and short-circuit conditions by turning off the external MOSFET in the event of a fault condition. The MAX5949A/MAX5949B also provide protection against input voltage steps. During an input voltage step, the MAX5949A/MAX5949B limit the current drawn by the load to a safe level without turning off power to the load. Both devices feature an open-drain power-good status output (PWRGD for the MAX5949A or PWRGD for the MAX5949B) that can be used to enable downstream converters. The MAX5949A/MAX5949B are available in an 8-pin SO package. Both devices are specified for the extended -40°C to +85°C temperature range. Applications Tele Line Cards Network Switches/Routers Central-Office Line Cards Server Line Cards Base-Station Line Cards Central-Office Switching -48V Distributed Power Systems Negative Power-Supply Controls Typical Operating Circuit and Selector Guide appear at end of data sheet. Features o Allow Safe Board Insertion and Removal from a Live -48V Backplane o Pin and Function patible with LT4250L (MAX5949A) o Pin patible with LT1640L (MAX5949A) o Pin and Function patible with LT4250H (MAX5949B) o Pin patible with LT1640H...