Digital Power Monitor with Convert Pin and ALERTB Output Data Sheet ADM1191 FEATURES FUNCTIONAL BLOCK DIAGRAM Powered from 3.15 V to 26 V CONV ADM1191 Precision current sense amplifier Precision voltage input SDA V VCC 0 12-bit ADC for current and voltage readback 2 SCL 12-BIT I C ADC Convert (CONV) pin for commanding an ADC read I A1 A 1 SETV input for setting overcurrent alert threshold SENSE MUX A0 ALERTB output provides an overcurrent interrupt CURRENT SENSE 2 I C fast mode-compliant interface (400 kHz maximum) AMPLIFIER 2 address pins allow 16 devices on the same bus 10-lead MSOP ALERT ALERTB SETV APPLICATIONS COMPARATOR Power monitoring/power budgeting GND Central office equipment Figure 1. Telecommunications and data communications equipment PCs/servers 3.15V TO 26V R SENSE GENERAL DESCRIPTION The ADM1191 is an integrated current sense amplifier that offers digital current and voltage monitoring via an on-chip VCC SENSE CONTROLLER 12-bit analog-to-digital converter (ADC), communicated ALERTB INTERRUPT 2 through an I C interface. ADM1191 P = VI SDA SDA SETV An internal current sense amplifier measures voltage across the SCL SCL sense resistor in the power path via the VCC pin and the SENSE pin. CONV CONV A 12-bit ADC can measure the current seen in the sense A1 GND A0 resistor, as well as the supply voltage on the VCC pin. 2 An industry-standard I C interface allows a controller to read Figure 2. Applications Diagram current and voltage data from the ADC. Measurements can be 2 initiated by an I C command or via the convert (CONV) pin. The CONV pin is especially useful for synchronizing reads on The ALERTB output can be used as a flag to warn a micro- multiple ADM1191 devices. Alternatively, the ADC can run controller or field programmable gate array (FPGA) of an continuously, and the user can read the latest conversion data overcurrent condition. ALERTB outputs of multiple ADM1191 2 whenever it is required. Up to 16 unique I C addresses can be devices can be tied together and used as a combined alert. created, depending on the way the A0 pin and the A1 pin are The ADM1191 is packaged in a 10-lead MSOP. connected. A SETV pin is also included. A voltage applied to this pin is internally compared with the output voltage on the current sense amplifier. The output of the SETV comparator asserts when the current sense amplifier output exceeds the SETV voltage. When this event occurs, the ALERTB output asserts. Rev. C 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. Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 20062012 Analog Devices, Inc. All rights reserved. 05804-002 05804-001ADM1191 Data Sheet TABLE OF CONTENTS 2 Features .............................................................................................. 1 Identifying the ADM1191 on the I C Bus ..................................9 2 Applications ....................................................................................... 1 General I C Timing .......................................................................9 General Description ......................................................................... 1 Write and Read Operations ........................................................... 11 Functional Block Diagram .............................................................. 1 Quick Command ........................................................................ 11 Revision History ............................................................................... 2 Write Command Byte ................................................................ 11 Specifications ..................................................................................... 3 Write Extended Command Byte .............................................. 12 Absolute Maximum Ratings ............................................................ 5 Read Voltage and/or Current Data Bytes ................................ 13 Thermal Characteristics .............................................................. 5 Applications Information .............................................................. 15 ESD Caution .................................................................................. 5 ALERTB Output ......................................................................... 15 Pin Configuration and Function Descriptions ............................. 6 SETV Pin ..................................................................................... 15 Typical Performance Characteristics ............................................. 7 Kelvin Sense Resistor Connection ........................................... 15 Voltage and Current Readback ....................................................... 9 Outline Dimensions ....................................................................... 16 Serial Bus Interface ....................................................................... 9 Ordering Guide .......................................................................... 16 REVISION HISTORY 6/12Rev. B to Rev. C 4/07Rev. 0 to Rev. A Added V = 3.0 V to 5.5 V Condition to V and V , Table 1 .. 4 Changes to Table 1 ............................................................................. 3 BUS IL IH Changed SETV Pin Rating from 30 V to 6 V, Table 2 ................. 5 Changes to Table 5 ............................................................................. 9 Changes to Pin 3, Pin 5, and Pin 10 Descriptions ........................ 6 Changes to Figure 16 and Figure 17 ............................................ 10 Changes to Bit 2, Table 9 ................................................................ 12 Changes to Figure 21 ...................................................................... 12 Changes to ALERTB Output Section ........................................... 15 Changes to Figure 23 and Figure 24 ............................................ 13 Changes to Kelvin Sense Resistor Connection Section ............. 15 Added Applications Information Heading ................................. 15 Deleted Figure 27 ............................................................................ 15 9/06Revision 0: Initial Version Updated Outline Dimensions ....................................................... 16 2/08Rev. A to Rev. B Changed V to V Throughout ................................................. 3 VCC CC Added ADC Conversion Time Parameter .................................... 3 Changes to Input Current for 00 Decode, IADRLOW, Parameter ... 4 Changes to Input Current for 11 Decode, IADRHIGH, Parameter ... 4 Added Endnote 2 .............................................................................. 4 Changes to Figure 6 .......................................................................... 7 2 Changes to Identifying the ADM1191 on the I C Bus Section ......... 9 2 Changes to General I C Timing Section, Step 3 ........................... 9 Changes to Table 5 ............................................................................ 9 Changes to Figure 16 and Figure 17 ............................................. 10 Changes to Quick Command Section ......................................... 11 Changes to Figure 19 ...................................................................... 11 Changes to Table 7 .......................................................................... 11 Changes to Write Extended Command Byte Section ................ 12 Changes to Figure 21 ...................................................................... 12 Changes to Table 9 and Table 11 ................................................... 12 Changes to Converting ADC Codes to Voltage and Current Readings Section ......................................................... 13 Changes to Figure 25 ...................................................................... 15 Change to SETV Pin Section ........................................................ 15 Rev. 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