High Voltage Input Protection Device Data Sheet ADM1270 FEATURES SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM VCC/SENSE+ SENSE Controls supply voltages from 4 V to 60 V Gate drive for low voltage drop reverse supply protection RPFG Gate drive for P-channel FETs ADM1270 Inrush current limiting control VCAP LDO + Adjustable current limit Foldback current limiting I OUT Automatic retry or latch-off on current fault UV + Programmable current-limit timer for safe operating area (SOA) 1V GATE DRIVE/ Power-good and fault outputs GATE LOGIC OV Analog undervoltage (UV) and overvoltage (OV) protection + 16-lead, 3 mm 3 mm LFCSP 1V 16-lead QSOP APPLICATIONS REF FLB ISET SELECT CURRENT LIMIT Industrial modules + CURRENT- Battery-powered/portable instrumentation FB PG LIMIT TIMER CONTROL ON GENERAL DESCRIPTION TIMER OFF TIMER The ADM1270 is a current-limiting controller that provides TIMER TIMEOUT V CB inrush current limiting and overcurrent protection for modular ENABLE PWRGD GND or battery-powered systems. When circuit boards are inserted FAULT into a live backplane, discharged supply bypass capacitors draw Figure 1. large transient currents from the backplane power bus as they charge. These transient currents can cause permanent damage to connector pins, as well as dips on the backplane supply that can reset other boards in the system. The ADM1270 is designed to control the inrush current, when powering on the system, via an external P-channel field effect transistor (FET). To protect the system from a reverse polarity input supply, there is a provision made to control an additional external P-channel FET. This feature prevents reverse current flow in case of a reverse polarity connection, which can damage the load or the ADM1270. The ADM1270 is available in a 3 mm 3 mm, 16-lead LFCSP and a 16-lead QSOP. Rev. A 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. No Tel: 781.329.4700 20142016 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com 12259-001ADM1270 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Current Sense Inputs ................................................................. 16 Applications ....................................................................................... 1 Current-Limit Reference ........................................................... 16 General Description ......................................................................... 1 Setting the Current Limit (ISET) ............................................. 16 Simplified Functional Block Diagram ........................................... 1 Foldback ...................................................................................... 17 Revision History ............................................................................... 2 TIMER ......................................................................................... 17 Specifications ..................................................................................... 3 TIMER OFF ............................................................................... 18 Absolute Maximum Ratings ............................................................ 5 Hot Swap Retry Duty Cycle ...................................................... 18 Thermal Characteristics .............................................................. 5 Gate and RPFG Clamps ............................................................. 19 ESD Caution .................................................................................. 5 Fast Response to Severe Overcurrent ...................................... 19 Pin Configurations and Function Descriptions ........................... 6 Undervoltage and Overvoltage ................................................. 19 Typical Performance Characteristics ............................................. 9 Enable Input ................................................................................ 19 Typical Application Circuit ........................................................... 14 Power Good ................................................................................ 20 Theory of Operation ...................................................................... 15 Outline Dimensions ....................................................................... 21 Powering the ADM1270 ............................................................ 16 Ordering Guide .......................................................................... 21 REVISION HISTORY 4/16Rev. 0 to Rev. A Change to Setting the Current Limit (ISET) Section ................. 17 12/14Revision 0: Initial Version Rev. A Page 2 of 21