MAX8535/MAX8536/MAX8585 19-2735 Rev 1 3/04 ORing MOSFET Controllers with Fastest Fault Isolation for Redundant Power Supplies General Description Features Critical loads often employ parallel-connected power Simple, Integrated, and Inexpensive ORing supplies with redundancy in order to enhance system MOSFET Controller reliability. The MAX8535/MAX8536/MAX8585 are highly ORing MOSFET Drive for 12V integrated but inexpensive MOSFET controllers that pro- vide isolation and redundant power capability in high-reli- (MAX8535/MAX8585) and 3.3V or 5V ability systems. The MAX8535/MAX8585 are used in 12V (MAX8536) Bus systems, and have an internal charge pump to drive the Eliminates ORing Diode Power Dissipation and gates of the n-channel pass elements to V + 10V. The CC Reverse Leakage Current MAX8536 is used in 3.3V and 5V systems, with a charge- pump output of V + 5V. Provides N + 1 Redundant Supply Capability for CC Highly Reliable Systems During startup, the MAX8535/MAX8536/MAX8585 moni- tor the voltage drop across external MOSFETs. Once Isolates Failed Supply from Output Bus in <1s V approaches or exceeds the bus voltage, the CC Reverse-Current Flow Detection MOSFETs are turned on. The MAX8535/MAX8536/ MAX8585 feature a dual-purpose TIMER input. A single Programmable Soft-Start external resistor from TIMER to ground sets the turn-on Logic-Enable Input speed of the external MOSFETs. Optionally, the TIMER input can be used as a logic-enable pin. Once the Adjustable Overvoltage and Undervoltage Trip device is turned on, the MAX8535/MAX8536/MAX8585 Points monitor the load, protecting against overvoltage, under- voltage, and reverse-current conditions. Fault-Indicator Output Overvoltage and undervoltage fault thresholds are Space-Saving 8-Pin MAX Package adjustable and can be disabled. The current-limit trip points are set by the external MOSFETs R , Ordering Information DS(ON) reducing component count. An open-drain logic-low PART TEMP RANGE PIN-PACKAGE fault output indicates if an overvoltage, undervoltage, or MAX8535EUA -40C to +85C 8 MAX reverse-current fault occurs. MAX8535AEUA -40C to +85C 8 MAX All devices come in a space-saving 8-pin MAX package and are specified over the extended -40C to MAX8536EUA -40C to +85C 8 MAX +85C temperature range. MAX8585EUA -40C to +85C 8 MAX Typical Operating Circuit MAX is a registered trademark of Maxim Integrated Products, Inc. OUTPUT: Applications 3.3V/5V +V -V O O (MAX8536), Silver Box Supplies for Servers 12V (MAX8535) OUT+ On-Board Redundant Power Supplies in Blade Servers Network/Telecom Power Supplies Rectifiers SILVER BOX OR Redundant Power Supplies in High-Availability GATE CS RECTIFIERS Systems V FAULT CC MAX8535 MAX8536 UVP N.C. MAX8585 TIMER OVP GND Pin Configuration, Functional Diagrams, and Typical Application Circuits appear at end of data sheet. OUT- Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE REDUNDANT OUTPUT BUSORing MOSFET Controllers with Fastest Fault Isolation for Redundant Power Supplies ABSOLUTE MAXIMUM RATINGS GATE to GND (MAX8535/MAX8535A/MAX8585)...-0.3V to +28V Continuous Power Dissipation (T = +70C) A V to GND (MAX8535/MAX8535A/MAX8585) .....-0.3V to +18V 8-Pin MAX (derate 4.5mW/C above +70C) .............362mW CC CS, FAULT to GND Operating Temperature Range ...........................-40C to +85C (MAX8535/MAX8535A/MAX8585)......................-0.3V to +15V Storage Temperature Range .............................-65C to +150C GATE to GND (MAX8536) ............................ -0.3V to (V + 6V) Junction Temperature ...........................................+150C CC V , CS, FAULT to GND (MAX8536) .......................-0.3V to +6V Lead Temperature (soldering, 10s) .................................+300C CC OVP, UVP, TIMER to GND........................................-0.3V to +6V Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 12V (MAX8535/MAX8535A/MAX8585), V = 5V (MAX8536), V = V - 0.1V, R = 25k , UVP = 2V, OVP = 1V, C CC CC CS CC TIMER GATE = 0.01F, T = 0C to +85C, unless otherwise noted.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V SUPPLY CC V = 14V (MAX8535/ CC 2 4.5 MAX8535A/MAX8585) V Supply Current TIMER = 2.5V mA CC V = 6V (MAX8536) 2 3 CC V = 14V (MAX8535/ CC 4.5 MAX8535A/MAX8585) V Shutdown Current TIMER = 0V mA CC V = 6V (MAX8536) 3 CC MAX8535/MAX8535A/ 814 MAX8585, charge pump on V Input Voltage TIMER = 2.5V MAX8536, charge pump on 3.0 5.5 V CC MAX8535/MAX8535A/ 17 MAX8585, charge pump off CS = 14V (MAX8535/ 100 MAX8535A/MAX8585) CS Input Current TIMER = 2.5V A CS = 5.5V (MAX8536) 50 CS Isolation C S = m ax oper at ing vo ltag e, V = 0V, I( V ) -0.05 -1 A C C C C MAX8535/MAX8535A/MAX8585, rising 6 6.5 7 threshold V Undervoltage Lockout V V CC CCOK MAX8536, rising threshold 2.5 2.7 2.9 MAX8535/ Rising threshold 14 14.5 15 V Overvoltage Internal CC MAX8535A/ V Threshold MAX8585 Falling threshold 13.3 13.9 14.5 CHARGE-PUMP VOLTAGE Measured from V to V , V = 3.3V GATE CC CC 5 5.5 6 (MAX8536) Gate Voltage V V GATE V = 5V (MAX8536) 5 5.5 6 CC V = 12V ( M AX853 5/M AX85 35A/M AX85 85) 911 12 C C 2 MAX8535/MAX8536/MAX8585