2.7 V to 16.5 V Hot Swap Controller with Power-Fail Comparator Data Sheet ADM1172 FEATURES GENERAL DESCRIPTION Controls supply rails from 2.7 V to 16.5 V The ADM1172 is a hot swap controller that safely enables a Allows protected board removal and insertion to a live printed circuit board to be removed and inserted to a live backplane backplane. This is achieved using an external N-channel power External sense resistor provides adjustable analog current MOSFET with a current control loop that monitors the load limit with circuit breaker current through a sense resistor. An internal charge pump is Peak fault current limited with fast response used to enhance the gate of the N-channel FET. When an over- Charge pumped gate drive for external N-FET switch current condition is detected, the gate voltage of the FET is Power-fail comparator reduced to limit the current flowing through the sense resistor. Automatic retry or latch-off during current fault During an overcurrent condition, the TIMER pin capacitor Undervoltage lockout determines the amount of time the FET remains at a current 8-lead, TSOT package limiting mode of operation until it is shut down. The ON (ON-CLR) pin is the enable input for the device and can be APPLICATIONS used to monitor the input supply voltage. The ADM1172 Hot swap board insertion: line cards, raid systems operates with a supply voltage ranging from 2.7 V to 16.5 V. Industrial high-side switches/circuit breakers The ADM1172 also features a power-fail comparator. The Electronic circuit breakers voltage on the PFI pin is compared with an internal 0.6 V reference, and the output of this comparator is presented on the PFO pin. This device is available in two options: the ADM1172-1 with automatic retry for overcurrent fault and the ADM1172-2 with latch-off for an overcurrent fault. Toggling CLR the ON (ON- ) pin resets a latched fault. The ADM1172 is packaged in an 8-lead TSOT. FUNCTIONAL BLOCK DIAGRAM R SENSE Q LONG 1 V = 5V V = 5V IN OUT C LOAD V SENSE CC R ON1 SHORT R PR1 ON GATE ADM1172-1 PFI R ON2 PFO TIMER GND R PR2 C TIMER GND LONG GND Figure 1. Rev. B Document Feedback Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. Tel: 781.329.4700 20062020 Analog Devices, Inc. All rights reserved. No license is granted by implication or otherwise under any patent or patent rights of Analog Technical Support www.analog.com Devices. Trademarks and registered trademarks are the property of their respective owners. 05126-001ADM1172 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 UVLO ........................................................................................... 12 Applications ...................................................................................... 1 ON (ON-CLR) Pin ..................................................................... 12 General Description ......................................................................... 1 GATE ........................................................................................... 12 Functional Block Diagram .............................................................. 1 Current Limit Function ............................................................. 12 Revision History ............................................................................... 2 Calculating the Current Limit .................................................. 12 Specifications .................................................................................... 3 Circuit Breaker Function .......................................................... 12 Absolute Maximum Ratings ........................................................... 4 Timer Function .......................................................................... 13 Thermal Characteristics .............................................................. 4 Power-Up Timing Cycle ........................................................... 13 ESD Caution.................................................................................. 4 Circuit Breaker Timing Cycle .................................................. 14 Pin Configurations and Function Descriptions ........................... 5 Automatic Retry or Latched Off .............................................. 14 Typical Performance Characteristics ............................................. 6 Power-Fail Comparator ............................................................ 14 Theory of Operation ...................................................................... 12 Outline Dimensions ....................................................................... 15 Overview ...................................................................................... 12 Ordering Guide .......................................................................... 15 REVISION HISTORY 3/2020Rev. A to Rev. B 3/2014Rev. 0 to Rev. A Change to Table 4 ............................................................................. 5 Changes to Figure 41 ..................................................................... 14 Change to On (ON-CLR) Pin Section ......................................... 12 Changes to Ordering Guide .......................................................... 15 7/2006Revision 0: Initial Version Rev. B Page 2 of 16