MIC2085/MIC2086 Single Channel Hot Swap Controllers - Micrel - #2

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Micrel, Inc. MIC2085/2086 May 2006 2 M9999-050406 (408) 955-1690 Ordering Information Part Number Standard Pb-Free Fast Circuit Breaker Threshold Discharge Output Package MIC2085-xBQS MIC2085-xYQS x = J, 95mV x = K, 150mV* x = L, 200mV* x = M, Off NA 16-Pin QSOP MIC2086-xBQS MIC2086-xYQS x = J, 95mV x = K, 150mV* x = L, 200mV* x = M, Off Yes 20-Pin QSOP * Contact factory for availability. Pin Configuration MIC2085 MIC2086 16-Pin QSOP (QS) 20-Pin QSOP (QS) Pin Description Pin Number MIC2086 Pin Number MIC2085 Pin Name Pin Function 1 1 CRWBR Overvoltage Timer and Crowbar Circuit Trigger: A capacitor connected to this pin, sets the timer duration for which an overvoltage condition will trigger an external crowbar circuit. This timer begins when the OV input rises above its threshold as an internal 45ìA current source charges the capacitor. Once the voltage reaches 470mV, the current increases to 1.5mA. 2 2 CFILTER Current Limit Response Timer: A capacitor connected to this pin defines the period of time (tOCSLOW) in which an overcurrent event must last to signal a fault condition and trip the circuit breaker. If no capacitor is connected, then tOCSLOW defaults to 5ìs. 3 3 CPOR Power-On Reset Timer: A capacitor connected between this pin and ground sets the start-up delay (tSTART) and the power-on reset interval (tPOR). When VCC rises above the UVLO threshold, the capacitor connected to CPOR begins to charge. When the voltage at CPOR crosses 1.24V, the start-up threshold (VSTART), a start cycle is initiated if ON is asserted while capacitor CPOR is immediately discharged to ground. When the voltage at FB rises above VFB, capacitor CPOR begins to charge again. When the voltage at CPOR rises above the power-on reset delay threshold (VTH), the timer resets by pulling CPOR to ground, and /POR is deasserted. If CPOR = 0, then tSTART defaults to 20ìs.