MAX8535

19-2735; Rev 1; 3/04 K ATION EVALU BLE AVAILA IT ORing MOSFET Controllers with Fastest Fault Isolation for Redundant Power Supplies General Description Features ♦ Simple, Integrated, and Inexpensive ORing MOSFET Controller ♦ ORing MOSFET Drive for 12V (MAX8535/MAX8585) and 3.3V or 5V (MAX8536) Bus ♦ Eliminates ORing Diode Power Dissipation and Reverse Leakage Current ♦ Provides N + 1 Redundant Supply Capability for Highly Reliable Systems ♦ Isolates Failed Supply from Output Bus in <1µs ♦ Reverse-Current Flow Detection ♦ Programmable Soft-Start ♦ Logic-Enable Input ♦ Adjustable Overvoltage and Undervoltage Trip Points ♦ Fault-Indicator Output ♦ Space-Saving 8-Pin µMAX Package MAX8535/MAX8536/MAX8585 Critical loads often employ parallel-connected power supplies with redundancy in order to enhance system reliability. The MAX8535/MAX8536/MAX8585 are highly integrated but inexpensive MOSFET controllers that provide isolation and redundant power capability in high-reliability systems. The MAX8535/MAX8585 are used in 12V systems, and have an internal charge pump to drive the gates of the n-channel pass elements to VCC + 10V. The MAX8536 is used in 3.3V and 5V systems, with a chargepump output of VCC + 5V. During startup, the MAX8535/MAX8536/MAX8585 monitor the voltage drop across external MOSFETs. Once V CC approaches or exceeds the bus voltage, the MOSFETs are turned on. The MAX8535/MAX8536/ MAX8585 feature a dual-purpose TIMER input. A single external resistor from TIMER to ...