Description

The MAX16545B/C is a circuit-breaker protection IC with anintegrated low-resistance MOSFET and lossless current-sensecircuitry featuring PMBus™ /SMBus control and reporting. TheIC is designed to provide the optimum solution for distribution,control, monitoring and protection of the system’s 12V powersupply. An internal LDO provides the bias supply voltage forthe protection IC.If no fault is detected, the MAX16545B/C initiates the startup.The device has been designed to provide controlled, monotonicstartup. Programmable soft-start ramp and delay is implementedto limit the inrush current during startup. The MAX16545B is setfor 16A Startup OCP, and the MAX16545C is set for 24A StartupOCP.The IC monitors the current and the voltage of the 12V systempower rail and provides multiple levels of protection with fastturn off if a fault is detected. Three methods of overcurrentprotection are provided. Programmable moderate OCP levelallows surge currents for a limited time. User-selectable severeOCP level provides a fast disconnect if a current exceedingthe severe OCP threshold is detected. An additional fixed highshutdown OCP level provides instantaneous disconnect tofurther protect the device.The lossless current sense provides high-accuracy currentsensing over load and temperature, improving overall systemenergy efficiency, and reducing dissipation. A signal proportionalto the load current is reported through an analog output andextensive reporting is provided through the SMBus/PMBus.Output voltage is monitored at all times. If at any time theoutput voltage falls below the programmable output undervoltagelockout threshold, the PWRGD signal is asserted low. Ifat any time the input voltage falls below the programmableinput undervoltage lockout threshold, the PWRGD signalis asserted low. The MAX16545B/C can be programmedthrough PMBus to provide input overvoltage protection. Inputovervoltage protection is disabled by default. When enabledthrough PMBus, if the input voltage exceeds a programmableovervoltage threshold, the MOSFET is latched off and a faultis communicated.The IC is used to distribute and control power to a systemfrom the +12V power supply.ApplicationsIntegrated Protection IC on 12V: Circuit Breaker, Hot Swap, Inrush ControlServers, Networking, Storage, Communication Equipment and AC/DC Power Supplies