Simple Sequencers in 6-Lead SC70 Data Sheet ADM1085/ADM1086/ADM1087 FEATURES FUNCTIONAL BLOCK DIAGRAMS Provide programmable time delays between enable V CC signals Can be cascaded with power modules for multiple ADM1085/ADM1086 supply sequencing V CAPACITOR IN Power supply monitoring from 0.6 V ADJUSTABLE ENOUT DELAY 0.6V Output stages High voltage (up to 22 V) open-drain output (ADM1085/ADM1087) Push-pull output (ADM1086) GND CEXT ENIN Capacitor-adjustable time delays High voltage (up to 22 V) enable and V inputs IN V CC Low power consumption (15 A) Specified over 40C to +125C temperature range ADM1087 6-lead SC70 package V IN CAPACITOR ADJUSTABLE ENOUT DELAY 0.6V APPLICATIONS Desktop/notebook computers, servers Low power portable equipment Routers GND CEXT ENIN Base stations Figure 1. Line cards Graphics cards GENERAL DESCRIPTION The ADM1085/ADM1086/ADM1087 are simple sequencing All four models have a dedicated enable input pin that allows circuits that provide a time delay between the enabling of the output signal to the regulator to be controlled externally. voltage regulators and/or dc-dc converters at power-up in This is an active high input (ENIN) for the ADM1085 and multiple supply systems. When the output voltage of the first ADM1086, and an active low input (ENIN) for the ADM1087. power module reaches a preset threshold, a time delay is The Simple Sequencers are specified over the extended initiated before an enable signal allows subsequent regulators to 40C to +125C temperature range. With low current power up. Any number of these devices can be cascaded with consumption of 15 A (typical) and 6-lead SC70 packaging, regulators to allow sequencing of multiple power supplies. the parts are suitable for low-power portable applications. Threshold levels can be set with a pair of external resistors in a Table 1. Selection Table voltage divider configuration. With appropriate resistor values, Output Stage the threshold can be adjusted to monitor voltages as low as 0.6 V. Part No. Enable Input ENOUT ENOUT The ADM1086 has a push-pull output stage, with active high ADM1085 ENIN Open-drain (ENOUT). The ADM1085 has an active-high (ENOUT) logic ADM1086 ENIN Push-pull output the ADM1087 has an active-low (ENOUT) output. Both the ADM1085 and ADM1087 have open-drain output stages ADM1087 ENIN Open-drain that can be pulled up to voltage levels as high as 22 V through an external resistor. This level-shifting property ensures compatibility with enable input logic levels of different regulators and converters. 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. No Tel: 781.329.4700 20042014 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 04591-001ADM1085/ADM1086/ADM1087 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Capacitor-Adjustable Delay Circuit ............................................9 Applications ....................................................................................... 1 Open-Drain and Push-Pull Outputs ....................................... 10 Functional Block Diagrams ............................................................. 1 Application Information ................................................................ 11 General Description ......................................................................... 1 Sequencing Circuits ................................................................... 11 Revision History ............................................................................... 2 Dual LOFO Sequencing ............................................................ 13 Specif icat ions ..................................................................................... 3 Simultaneous Enabling .............................................................. 13 Absolute Maximum Ratings ............................................................ 4 Power Good Signal Delays ........................................................ 13 ESD Caution .................................................................................. 4 Quad-Supply Power Good Indicator ....................................... 14 Pin Configuration and Function Descriptions ............................. 5 Sequencing with FET Switches ................................................. 14 Typical Performance Characteristics ............................................. 6 Outline Dimensions ....................................................................... 15 Circuit Information .......................................................................... 9 Ordering Guide .......................................................................... 15 Timing Characteristics and Truth Tables .................................. 9 REVISION HISTORY 5/14Rev. A to Rev. B Removed ADM1088 ...................................................... Throughout Changes to Capacitor-Adjustable Delay Circuit........................... 9 Removed Figure 26 Renumbered Sequentially.......................... 12 Changes to Ordering Guide .......................................................... 15 4/06Rev. 0 to Rev. A Added Lead-Free Models .................................................. Universal Update Outline Dimensions ......................................................... 15 Changes to Ordering Guide .......................................................... 15 7/04Revision 0: Initial Version Rev. B Page 2 of 16