/ / 256-Position, One-Time Programmable, 2 Dual-Channel, I C Digital Potentiometers Data Sheet AD5172/AD5173 FEATURES FUNCTIONAL BLOCK DIAGRAMS A1 W1 B1 A2 W2 B2 2-channel, 256-position potentiometers One-time programmable (OTP) set-and-forget resistance setting provides a low cost alternative to EEMEM Unlimited adjustments prior to OTP activation OTP overwrite allows dynamic adjustments with user- FUSE V DD LINKS defined preset 12 End-to-end resistance: 2.5 k, 10 k, 50 k, and 100 k RDAC RDAC GND Compact 10-lead MSOP: 3 mm 4.9 mm REGISTER 1 REGISTER 2 Fast settling time: t = 5 s typical on power-up S Full read/write of wiper register 8 Power-on preset to midscale SDA SERIAL INPUT Extra package address decode pins: AD0 and AD1 (AD5173 ) REGISTER SCL Single supply: 2.7 V to 5.5 V Figure 1. AD5172 Functional Block Diagram Low temperature coefficient: 35 ppm/C W1 B1 W2 B2 Low power: I = 6 A maximum DD Wide operating temperature: 40C to +125C APPLICATIONS Systems calibration FUSE V DD LINKS 12 Electronics level setting Mechanical trimmers replacement in new designs RDAC RDAC GND REGISTER 1 REGISTER 2 Permanent factory PCB setting Transducer adjustment of pressure, temperature, position, AD0 chemical, and optical sensors ADDRESS DECODE AD1 8 RF amplifier biasing Automotive electronics adjustment SDA SERIAL INPUT Gain control and offset adjustment REGISTER SCL Figure 2. AD5173 Functional Block Diagram GENERAL DESCRIPTION The AD5172/AD5173 are dual-channel, 256-position, one-time before permanently setting the resistance value. During OTP 1 programmable (OTP) digital potentiometers that employ fuse activation, a permanent blow fuse command freezes the wiper link technology to achieve memory retention of resistance position (analogous to placing epoxy on a mechanical trimmer). settings. OTP is a cost-effective alternative to EEMEM for users Unlike traditional OTP digital potentiometers, the AD5172/ who do not need to program the digital potentiometer setting AD5173 have a unique temporary OTP overwrite feature that in memory more than once. These devices perform the same allows for new adjustments even after a fuse is blown. However, electronic adjustment function as mechanical potentiometers or the OTP setting is restored during subsequent power-up condi- variable resistors but with enhanced resolution, solid-state reliabil- tions. This allows users to treat these digital potentiometers as ity, and superior low temperature coefficient performance. volatile potentiometers with a programmable preset. 2 The AD5172/AD5173 are programmed using a 2-wire, I C- compatible digital interface. Unlimited adjustments are allowed 1 The terms digital potentiometer, VR, and RDAC are used interchangeably. Rev. I 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 20032013 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. 04103-002 04103-001AD5172/AD5173 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Programming the Variable Resistor and Voltage ................... 16 Applications ....................................................................................... 1 Programming the Potentiometer Divider ............................... 17 Functional Block Diagrams ............................................................. 1 ESD Protection ........................................................................... 18 General Description ......................................................................... 1 Terminal Voltage Operating Range ......................................... 18 Revision History ............................................................................... 3 Power-Up Sequence ................................................................... 18 Specifications ..................................................................................... 4 Power Supply Considerations ................................................... 18 Electrical Characteristics: 2.5 k ............................................... 4 Layout Considerations ............................................................... 19 2 Electrical Characteristics: 10 k, 50 k, and 100 k ............. 5 I C Interface .................................................................................... 20 Timing Characteristics ................................................................ 7 Write Mode ................................................................................. 20 Absolute Maximum Ratings ............................................................ 8 Read Mode .................................................................................. 20 2 ESD Caution .................................................................................. 8 I C Controller Programming .................................................... 21 2 Pin Configurations and Function Descriptions ........................... 9 I C-Compatible, 2-Wire Serial Bus .......................................... 22 Typical Performance Characteristics ........................................... 10 Level Shifting for Different Voltage Operation ...................... 23 Test Circuits ..................................................................................... 15 Outline Dimensions ....................................................................... 24 Theory of Operation ...................................................................... 16 Ordering Guide .......................................................................... 25 One-Time Programming (OTP) .............................................. 16 Rev. I Page 2 of 28