2 Quad 64-/256-Position I C Nonvolatile Memory Digital Potentiometers Data Sheet AD5253/AD5254 FEATURES FUNCTIONAL BLOCK DIAGRAM AD5253: quad 64-position resolution RDAC EEMEM V RDAC0 DD AD5254: quad 256-position resolution A0 RDAC0 V SS EEMEM REGIS- W0 1 k , 10 k , 50 k , 100 k R TOL POWER-ON AB TER DGND 1 B0 REFRESH Nonvolatile memory stores wiper settings w/write protection WP Power-on refreshed to EEMEM settings in 300 s typ DATA RDAC1 A1 SCL RDAC1 EEMEM rewrite time = 540 s typ 2 SDA I C REGIS- W1 SERIAL TER Resistance tolerance stored in nonvolatile memory CONTROL B1 INTERFACE AD0 COMMAND 12 extra bytes in EEMEM for user-defined information DECODE LOGIC RDAC2 AD1 2 A2 RDAC2 I C-compatible serial interface ADDRESS REGIS- W2 2 Direct read/write access of RDAC and EEMEM registers DECODE LOGIC TER B2 Predefined linear increment/decrement commands CONTROL LOGIC RDAC3 Predefined 6 dB step change commands A3 RDAC3 REGIS- W3 Synchronous or asynchronous quad-channel update TER AD5253/AD5254 B3 Wiper setting readback 4 MHz bandwidth1 k version Single supply 2.7 V to 5.5 V Figure 1. Dual supply 2.25 V to 2.75 V 2 slave address-decoding bits allow operation of 4 devices 2 The AD5253/AD5254 allow the host I C controllers to write 100-year typical data retention, T = 55C A any of the 64-/256-step wiper settings in the RDAC registers Operating temperature: 40C to +105C and store them in the EEMEM. Once the settings are stored, APPLICATIONS they are restored automatically to the RDAC registers at system Mechanical potentiometer replacement power-on the settings can also be restored dynamically. Low resolution DAC replacement The AD5253/AD5254 provide additional increment, RGB LED backlight control decrement, +6 dB step change, and 6 dB step change in White LED brightness adjustment synchronous or asynchronous channel update mode. The RF base station power amp bias control increment and decrement functions allow stepwise linear Programmable gain and offset control adjustments, with a 6 dB step change equivalent to doubling Programmable attenuators or halving the RDAC wiper setting. These functions are useful Programmable voltage-to-current conversion for steep-slope, nonlinear adjustments, such as white LED Programmable power supply brightness and audio volume control. Programmable filters Sensor calibrations The AD5253/AD5254 have a patented resistance-tolerance GENERAL DESCRIPTION storing function that allows the user to access the EEMEM and 2 The AD5253/AD5254 are quad-channel, I C, nonvolatile obtain the absolute end-to-end resistance values of the RDACs mem-ory, digitally controlled potentiometers with 64/256 for precision applications. positions, respectively. These devices perform the same The AD5253/AD5254 are available in TSSOP-20 packages in electronic adjust-ment functions as mechanical potentiometers, 1 k, 10 k, 50 k, and 100 k options. All parts are trimmers, and variable resistors. guaranteed to operate over the 40C to +105C extended The parts versatile programmability allows multiple modes of industrial temperature range. operation, including read/write access in the RDAC and EEMEM 1 The terms nonvolatile memory and EEMEM are used interchangeably. registers, increment/decrement of resistance, resistance changes 2 The terms digital potentiometer and RDAC are used interchangeably. in 6 dB scales, wiper setting readback, and extra EEMEM for storing user-defined information, such as memory data for other components, look-up table, or system identification information. Rev. C 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 20032012 Analog Devices, Inc. All rights reserved. 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. Technical Support www.analog.com 03824-0-001AD5253/AD5254 Data Sheet TABLE OF CONTENTS 2 Features .............................................................................................. 1 I C-Compatible 2-Wire Serial Bus ........................................... 20 Applications ....................................................................................... 1 Theory of Operation ...................................................................... 21 General Description ......................................................................... 1 Linear Increment/Decrement Commands ............................. 21 Functional Block Diagram .............................................................. 1 6 dB Adjustments (Doubling/Halving Wiper Setting) ....... 21 Revision History ............................................................................... 2 Digital Input/Output Configuration........................................ 22 Electrical Characteristics ................................................................. 3 Multiple Devices on One Bus ................................................... 22 1 k Version .................................................................................. 3 Terminal Voltage Operation Range ......................................... 23 10 k, 50 k, 100 k Versions .................................................. 5 Power-Up and Power-Down Sequences .................................. 23 Interface Timing Characteristics ................................................ 7 Layout and Power Supply Biasing ............................................ 23 Absolute Maximum Ratings ............................................................ 8 Digital Potentiometer Operation ............................................. 24 ESD Caution .................................................................................. 8 Programmable Rheostat Operation ......................................... 24 Pin Configuration and Function Descriptions ............................. 9 Programmable Potentiometer Operation ............................... 25 Typical Performance Characteristics ........................................... 10 Applications Information .............................................................. 26 2 I C Interface ..................................................................................... 14 RGB LED Backlight Controller for LCD Panels .................... 26 2 I C Interface General Description ............................................ 14 Outline Dimensions ....................................................................... 28 2 I C Interface Detail Description ............................................... 15 Ordering Guide .......................................................................... 29 REVISION HISTORY 9/12Rev. B to Rev. C 9/05Rev. 0 to Rev. A Changed Temperature Range from 40C to +85C to 40C Change to Figure 6 ......................................................................... 10 to +105C (Throughout).................................................................. 1 Change to EEMEM Write Protection Section ............................ 18 Changed WP Leakage Current from 5 A to 8 A, Table 1 ........ 4 Changes to Figure 37 ...................................................................... 22 Deleted Table 13 and Table 14 ...................................................... 24 Changed Leakage Current from 5 A to 8 A, Table 2 ........ 5 WP Change to Figure 43 ....................................................................... 25 Changes to Figure 11 and Figure 12 ............................................. 12 Changes to Ordering Guide .......................................................... 29 Changes to Ordering Guide .......................................................... 29 10/09Rev. A to Rev. B 5/03Revision 0: Initial Version Change to Figure 27 ....................................................................... 15 Rev. C Page 2 of 32