1024-/256-Position, 1% Resistor Tolerance Error, 2 I C Interface and 50-TP Memory Digital Rheostat Data Sheet AD5272/AD5274 FEATURES FUNCTIONAL BLOCK DIAGRAM V DD Single-channel, 1024-/256-position resolution 20 k, 50 k, 100 k nominal resistance Maximum 1% nominal resistor tolerance error POWER-ON RESET 50-times programmable (50-TP) wiper memory AD5272/AD5274 Rheostat mode temperature coefficient: 5 ppm/C 2.7 V to 5.5 V single-supply operation RDAC 2.5 V to 2.75 V dual-supply operation for ac or bipolar SCL REGISTER A 2 I C 10/8 operations SERIAL SDA 2 I C-compatible interface INTERFACE W Wiper setting readback 50-TP ADDR MEMORY Power on refreshed from 50-TP memory BLOCK RESET Thin LFCSP 10-lead, 3 mm 3 mm 0.8 mm package Compact MSOP, 10-lead 3 mm 4.9 mm 1.1 mm package V EXT CAP GND SS APPLICATIONS Figure 1. Mechanical rheostat replacements Op-amp: variable gain control Instrumentation: gain, offset adjustment Programmable voltage to current conversions Programmable filters, delays, time constants Programmable power supply Sensor calibration GENERAL DESCRIPTION 1 The AD5272/AD5274 are single-channel, 1024-/256-position The AD5272/AD5274 device wiper settings are controllable 2 digital rheostats that combine industry leading variable resistor through the I C-compatible digital interface. Unlimited performance with nonvolatile memory (NVM) in a compact adjustments are allowed before programming the resistance package. value into the 50-TP memory. The AD5272/AD5274 do not require any external voltage supply to facilitate fuse blow and The AD5272/AD5274 ensure less than 1% end-to-end resistor there are 50 opportunities for permanent programming. During tolerance error and offer 50-times programmable (50-TP) memory. 50-TP activation, a permanent blow fuse command freezes the The guaranteed industry leading low resistor tolerance error wiper position (analogous to placing epoxy on a mechanical feature simplifies open-loop applications as well as precision trimmer). calibration and tolerance matching applications. The AD5272/AD5274 are available in a 3 mm 3 mm 10-lead LFCSP package and in a 10-lead MSOP package. The parts are guaranteed to operate over the extended industrial temperature range of 40C to +125C. 1 Protected by U.S. Patent Number 7688240. Rev. D 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 20092013 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. 08076-001AD5272/AD5274 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Shift Register ............................................................................... 18 Applications ....................................................................................... 1 Write Operation.......................................................................... 19 Functional Block Diagram .............................................................. 1 Read Operation........................................................................... 20 General Description ......................................................................... 1 RDAC Register ............................................................................ 21 Revision History ............................................................................... 2 50-TP Memory Block ................................................................ 21 Specifications ..................................................................................... 3 Write Protection ......................................................................... 21 Electrical CharacteristicsAD5272 .......................................... 3 50-TP Memory Write-Acknowledge Polling .......................... 23 Electrical CharacteristicsAD5274 .......................................... 5 Reset ............................................................................................. 23 Interface Timing Specifications .................................................. 7 Resistor Performance Mode ...................................................... 23 Absolute Maximum Ratings ............................................................ 9 Shutdown Mode ......................................................................... 23 Thermal Resistance ...................................................................... 9 RDAC Architecture .................................................................... 23 ESD Caution .................................................................................. 9 Programming the Variable Resistor ......................................... 23 Pin Configuration and Function Descriptions ........................... 10 EXT CAP Capacitor .................................................................. 24 Typical Performance Characteristics ........................................... 11 Terminal Voltage Operating Range ......................................... 24 Test Circuits ..................................................................................... 17 Power-Up Sequence ................................................................... 24 Theory of Operation ...................................................................... 18 Outline Dimensions ....................................................................... 25 Serial Data Interface ................................................................... 18 Ordering Guide .......................................................................... 25 REVISION HISTORY 3/13Rev. C to Rev. D 3/10Rev. 0 to Rev. A Changed Resistor Noise Density, RAW = 20 k from 50 nV/Hz Changes to Product Title and General Description Section ....... 1 to 13 nV/Hz Table 1 ...................................................................... 4 Changes to Theory of Operation Section.................................... 15 Changed Resistor Noise Density, RAW = 20 k from 50 nV/Hz to 13 nV/Hz Table 4 ...................................................................... 6 10/09Revision 0: Initial Version Updated Outline Dimensions ....................................................... 25 11/10Rev. B to Rev. C Changes to Figure 24 ...................................................................... 14 5/10Rev. A to Rev. B Added LFCSP Package .................................................. Throughout Changed OTP to 50-TP ................................................ Throughout Changes to Features Section and Applications Section ............... 1 Added Endnote 1 .............................................................................. 1 Changes to Table 1 ............................................................................ 3 Added Table 3 .................................................................................... 4 Changes to Table 4 ............................................................................ 5 Added Table 6 .................................................................................... 6 Changes to Table 8 and Table 9 ....................................................... 9 Added Figure 5 ................................................................................ 10 Added Exposed Pad Note to Table 10 .......................................... 10 Changes to Typical Performance Characteristics ....................... 11 Changes to Resistor Performance Mode Section ....................... 23 Updated Outline Dimensions ....................................................... 25 Changes to Ordering Guide .......................................................... 26 Rev. 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