MIC2085 Single-Channel Low Voltage Hot Swap Controller Features General Description Pin-for-Pin Functional Equivalent to the LTC1642 The MIC2085 is a single channel, positive voltage, hot swap controller designed to allow the safe insertion of 2.3V to 16.5V Supply Voltage Operation boards into live system backplanes. The MIC2085 is Surge Voltage Protection to 33V available in a 16-pin QSOP package. Using a few Operating Temperature Range 40C to +85C external components and by controlling the gate drive Active Current Regulation Limits Inrush Current of an external N-Channel MOSFET device, the Independent of Load Capacitance MIC2085 provides inrush current limiting and output Programmable Inrush Current Limiting voltage slew rate control in harsh, critical power supply environments. Additionally, a circuit breaker function Analog Foldback Current Limiting will latch the output MOSFET off if the current limit Electronic Circuit Breaker threshold is exceeded for a programmed period of time. Dual-Level Overcurrent Fault Sensing The devices array of features provide a simplified yet Fast Response to Short-Circuit Conditions (<1s) robust solution for many network applications in Programmable Output Undervoltage Detection meeting the power supply regulation requirements and Undervoltage Lockout Protection affords protection of critical downstream devices and components. Power-On Reset /FAULT Status Output Package Type Driver for SCR Crowbar on Overvoltage MIC2085 16-Lead QSOP (QS) Applications (Top View) RAID Systems Cellular Base Stations CRWBR 1 16 VCC LAN Servers CFILTER 2 15 SENSE WAN Servers CPOR 3 14 GATE InfiniBand Systems ON 4 13 REF Industrial High-Side Switching /POR 5 12 COMP /FAULT 6 11 COMP+ FB 7 10 COMPOUT GND 8 9 OV 2019 Microchip Technology Inc. DS20006094A-page 1MIC2085 Typical Application Circuit R Q1 Backplane PCB Edge SENSE Long Connector Connector 0.007 Si7884DP Pin TM 2% (PowerPAK SO-8) V 12 IN V OUT 12V 12V 5A 34 R1 3.3 C LOAD C1 220F 1F R7 *R6 127k Short 10 1% Pin V LOGIC 16 15 VCC SENSE 14 GATE R5 R2 R10 R11 47k 100k 11 47k 47k COMP+ Output Signal 1% (Power Good) 4 10 COMPOUT PWRGD ON C2 LOGIC 6 /FAULT 0.022F /FAULT CONTROLLER 5 R3 MIC2085 /POR /RESET Medium 1.82k Power-On Reset 9 7 (or Short) 1% OV FB Output Pin R4 R8 12 10k COMP 16.2k 1% 1% 13 1 Q2 REF CRWBR 2N4401 Q3 C7 TCR22-4 CPOR GND CFILTER 0.033F 3 8 2 C3 C4 C5 C6 **R9 0.1F 0.1F 8200pF 0.01F 180 GND Long Pin Overvoltage (Input) = 13.3V POR/START-UP DELAY = 60ms Undervoltage Lockout = 10.8V Circuit-Breaker Response Time = 500s Undervoltage (Output) & *R6 is an optional component used for noise filtering Power-Good (Output) = 11.4V **R9 needed when using a sensitive gate SCR Functional Block Diagram Charge 14 GATE Pump 15 SENSE 21V 1.24V 16 VCC 13V 48mV 13 REG2 REF 10 COMPOUT 11 COMP+ 12 COMP 95mV V CC1 REG1 V CC1 V CC1 20A UVLO Circuit Breaker 20A 2.2V Response or 6 UVLO /FAULT V CC1 2 CFILTER 20A Logic 1.24V 5 /POR 8 GND V CC1 7 FB Glitch V 1.5mA Filter CC1 1.24V 45A V CC1 1 2.5A CRWBR 3 CPOR 1.24V 0.45V 4 9 ON Glitch OV Glitch Filter Filter 1.24V 1.24V DS20006094A-page 2 2019 Microchip Technology Inc.