MAX5923 19-2850 Rev 0 4/03 +60V Simple Swapper Hot-Swap Switch General Description Features The MAX5923 is a fully integrated Simple Swapper Wide Operating Input Range: +16V to +60V hot-swap switch for positive supply rails. The device 0.45 Integrated Power Switch allows the safe insertion and removal of circuit cards into live backplanes or ports without causing glitches Programmable Output Current Up to 800mA on the power-supply rail. The device also monitors vari- Over/Undercurrent-Limit Detection ous circuit parameters and disconnects the load if a fault condition occurs, alerting the host with a logic- Input Logic Signals Compatible with 1.8V to 5V level FAULT output. The MAX5923 operates over the CMOS Logic +16V to +60V input voltage range. Separate Analog and Digital Grounds with Up to During startup, an integrated 0.45 power MOSFET 4V Offset regulates the current and voltage between the back- plane power source and the load. After startup, the Power-OK Status Output MOSFET is fully enhanced to reduce its on-resistance. Overcurrent Protection with Status Outputs To ensure robust operation, the MAX5923 contains built-in safety features that monitor fault conditions and Built-In Thermal Shutdown prevent damage to the internal MOSFET. Internal Switch Protection Circuitry The MAX5923 monitors three parameters for fault condi- Current-Limit Foldback with Timeout and Duty- tions: zero current, overcurrent, and thermal overload. The output overcurrent limit counts the time the MAX5923 Cycle Control spends in an overcurrent condition and shuts down the Latch or Autorestart Fault Management pass transistor if the current limit is exceeded for the over- current time limit. The zero-current detection counts the time the output current is below the zero-current threshold Ordering Information and shuts down the pass transistor if the counter reaches the zero-current time limit. The thermal monitoring feature PART TEMP RANGE PIN-PACKAGE shuts down the pass transistor if the die temperature MAX5923EUP -40C to +85C 20 TSSOP reaches the overtemperature limit. A fault logic output indicates when an overtemperature or an overcurrent condition has occurred and a zero-current logic output Typical Operating Circuit indicates if there is a zero-current condition. An undervoltage detection circuitry keeps the pass tran- +16V TO +60V sistor off until the input voltage is above the undervoltage IN OUT lockout (UVLO) threshold, which is internally set or can be set externally with a resistive divider. A power-OK (POK) D1 R SENSE +1.65V TO +5.5V output is provided to signal when the output voltage has VDIG DRAIN reached to within 0.75V of the input voltage. An Enable R PU input allows the host system to disconnect the system MAX5923 UVLO from the load and/or reset a fault condition by toggling LATCH R PU Enable. ON ZC EN R PU The MAX5923 is available in a 20-pin TSSOP package OFF EN and operates in the extended -40C to +85C tempera- ZC ture range. FAULT POK Applications AGND S DGND Network Routers/Switches Servers Current Limiter Industrial Equipment ALL SIGNAL AND DIGITAL INPUTS/OUTPUTS ARE REFERENCED TO DGND. DGND CAN BE 4V FROM AGND S. Simple Swapper is a trademark of Maxim Integrated Products, Inc. Pin Configuration appears at end of data sheet. 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.+60V Simple Swapper Hot-Swap Switch ABSOLUTE MAXIMUM RATINGS All Voltages with Respect to AGND S, Unless Otherwise Noted DGND..........................................................................-5V to +5V IN............................................................................-0.3V to +76V Maximum Current into DRAIN...............................................0.8A UVLO........................................................................-0.3V to +6V Maximum Current into POK, ZC, FAULT (sinking)..............20mA VDIG to DGND .........................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A OUT .......................................................-0.3V to (V + 0.3V) 20-Pin TSSOP (derate 11.1mW/C above +70C) .......879mW DRAIN DRAIN..........................................................-0.3V to (V + 0.3V) Operating Temperature Range ...........................-40C to +85C IN EN, ZC EN, ZC, FAULT, POK Junction Temperature......................................................+150C and LATCH to DGND ...............................................-0.3V to +6V Storage Temperature Range .............................-65C to +160C Lead Temperature (soldering, 10s) .................................+300C 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 = 48V, VDIG = 3.3V, AGND S = AGND = DGND = 0V, R = 0.5 1%, UVLO = open, EN = VDIG, T = -40C to +85C, unless IN SENSE A otherwise noted. Typical values are at T = +25C.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Analog Input Voltage Range V 16 60 V IN V = 72V, measured at AGND after OUT IN Analog Input Supply Current I 1 1.6 mA IN has stopped slewing Digital Input Voltage Range V 1.65 5.5 V DIG Digital Input Supply Current I V = 5V 0.05 0.1 mA DIG DIG DGND-to-AGND Operating -4 +4 V Voltage Range Current-Limit Response Time OUT shorted to AGND (Note 1) 1 s OUT Current-Limit Foldback V (Note 2) 18 V FBSTOP Voltage Maximum voltage across R at V > SENSE OUT 198 212 225 Current-Limit Sense Voltage V V FBSTOP mV ILIM (V - V ) (Note 3) IN DRS 0C to +85C 203 212 221 V = 0V 64 70 76 OUT Current-Limit Sense Foldback V mV ILIM fb Voltage (V - V ) IN DRS 0C to +85C 506075 Overcurrent Timeout t OUT shorted to AGND (Note 4) 50 60 70 ms OC T = +25C 0.45 A D On-Resistance R I = 100mA MOS DSON OUT T = +85C 0.75 A Power-Off OUT Sink Current EN = DGND, V = 48V 15 A OUT Maximum Output Voltage Slew dV /dt, V rising, no load 100 V/ms OUT OUT Rate Maximum Output Current Slew dI /dt, V rising, C = 100F 35 A/ms OUT OUT LOAD Rate V rising, POK from low to high 650 750 850 mV OUT Power-OK Threshold (V - V )V IN OUT THPOK Hysteresis 10 % POK Output Low Voltage V I = 3mA 0.4 V POK LOW POK POK Output Leakage Current V = 3.3V 0.05 1 A POK 2 MAX5923