Quad Voltage Monitor and Sequencer ADM1185 FEATURES FUNCTIONAL BLOCK DIAGRAM VCC Powered from 2.7 V to 5.5 V on the VCC pin Monitors 4 supplies via 0.8% accurate comparators POWER AND REF = 0.6V Logical core with internal timeouts provides power supply REFERENCE ADM1185 GENERATOR sequencing and fault protection OUT1 4 inputs can be programmed to monitor different voltage VIN1 REF = 0.6V levels with resistor dividers 3 open-drain enable outputs OUT2 VIN2 Open-drain power-good output (PWRGD) REF = 0.6V 10-lead MSOP STATE OUT3 MACHINE APPLICATIONS VIN3 CORE REF = 0.6V Monitor and alarm functions PWRGD Power supply sequencing VIN4 Telecommunication and data communication equipment REF = 0.6V PCs/servers GND Figure 1. GENERAL DESCRIPTION The ADM1185 is an integrated, 4-channel, voltage monitoring Internal time delays can be used for sequencing the startup of and sequencing device. A 2.7 V to 5.5 V power supply is subsequent power supplies enabled by the outputs. Supplies required on the VCC pin to power the device. falling out of range are also detected and, as a result, appropriate outputs are disabled. Four precision comparators monitor four voltage rails. All comparators have a 0.6 V reference with a worst-case The ADM1185 has four open-drain outputs. In a typical accuracy of 0.8%. Resistor networks that are external to the configuration, OUT1 to OUT3 are used to enable power VIN1, VIN2, VIN3, and VIN4 pins set the trip points for supplies, while PWRGD is a common power-good output, the monitored supply rails. indicating the status of all monitored supplies. A digital core interprets the status of the comparator outputs. The ADM1185 is available in a 10-lead mini small outline package (MSOP). APPLICATIONS DIAGRAM 3.3V IN 2.5V OUT VCC IN 1.8V OUT ADM1185 REGULATOR1 2.5V OUT 1.2V OUT VIN1 OUT1 EN OUT GND VIN2 OUT2 IN REGULATOR2 VIN3 OUT3 1.8V OUT EN OUT VIN4 GND GND PWRGD IN REGULATOR3 1.2V OUT EN OUT GND POWER GOOD Figure 2. Rev. B 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 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 20072009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 06196-002 06196-001ADM1185 TABLE OF CONTENTS Features .............................................................................................. 1 ESD Caution...................................................................................4 Applications ....................................................................................... 1 Pin Configuration and Function Descriptions ..............................5 Functional Block Diagram .............................................................. 1 Typical Performance Characteristics ..............................................6 General Description ......................................................................... 1 Theory of Operation .........................................................................9 Applications Diagram ...................................................................... 1 Power-On Sequencing and Monitoring .....................................9 Revision History ............................................................................... 2 Voltage Monitoring After Power-On ....................................... 10 Specif icat ions ..................................................................................... 3 Cascading Multiple Devices ...................................................... 12 Absolute Maximum Ratings ............................................................ 4 Outline Dimensions ....................................................................... 13 Thermal Resistance ...................................................................... 4 Ordering Guide .......................................................................... 13 REVISION HISTORY /09Rev. A to Rev. B Changes to Input Rising Threshold, VTHR Parameter, Table 1 ................................................................................................ 3 11/07Rev. 0 to Rev. A Changes to Table 5 ............................................................................ 9 Changes to Figure 20 and Figure 21 ............................................. 11 3/07Revision 0: Initial Version Rev. B Page 2 of 16