2 128-Position I C-Compatible Digital Resistor Data Sheet AD5246 FEATURES FUNCTIONAL BLOCK DIAGRAM V 128-position DD End-to-end resistance 5 k, 10 k, 50 k, 100 k Ultracompact SC70-6 (2 mm 2.1 mm) package SCL 2 2 I C INTERFACE A I C compatible interface SDA Full read/write of wiper register W Power-on preset to midscale Single supply 2.7 V to 5.5 V B WIPER REGISTER Rheostat mode temperature coefficient: 45 ppm/C Low power, I = 0.9 A at 3.3 V typical DD Wide operating temperature 40C to +125C GND Figure 1. APPLICATIONS Mechanical potentiometer replacement in new designs Transducer adjustment of pressure, temperature, position, chemical, and optical sensors RF amplifier biasing Automotive electronics adjustment Gain control and offset adjustment GENERAL OVERVIEW The AD5246 provides a compact 2 mm 2.1 mm packaged solution for 128-position adjustment applications. This device performs the same electronic adjustment function as a variable resistor. Available in four different end-to-end resistance values (5 k, 10 k, 50 k, 100 k), these low temperature coefficient devices are ideal for high accuracy and stability variable resistance adjustments. 2 The wiper settings are controllable through the I C compatible digital interface, which can also be used to read back the present wiper register control word. The resistance between the wiper and either end point of the fixed resistor varies linearly with 1 respect to the digital code transferred into the RDAC latch. Operating from a 2.7 V to 5.5 V power supply and consuming 0.9 A (3.3 V) allows for usage in portable battery-operated applications. 1 The terms digital potentiometer, VR, and RDAC are used interchangeably in this document. 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 rights of third parties that may result from its use. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Specifications subject to change without notice. No license is granted by implication Tel: 781.329.4700 www.analog.com or otherwise under any patent or patent rights of Analog Devices. Trademarks and Fax: 781.461.3113 20032012 Analog Devices, Inc. All rights reserved. registered trademarks are the property of their respective owners. 03875-001AD5246 Data Sheet TABLE OF CONTENTS Specifications ..................................................................................... 3 Programming the Variable Resistor ......................................... 13 2 Electrical Characteristics5 k Version .................................. 3 I C Compatible 2-Wire Serial Bus ........................................... 13 Electrical Characteristics10 k, 50 k, 100 k Versions .. 4 Level Shifting for Bidirectional Interface ................................ 14 Timing Characteristics ................................................................ 5 ESD Protection ........................................................................... 14 Absolute Maximum Ratings ............................................................ 6 Terminal Voltage Operating Range ......................................... 14 ESD CAUTION ............................................................................ 6 Maximum Operating Current .................................................. 14 Pin Configuration and Function Descriptions ............................. 7 Power-Up Sequence ................................................................... 14 Typical Performance Characteristics ............................................. 8 Layout and Power Supply Bypassing ....................................... 15 Test Circuits ..................................................................................... 11 Constant Bias to Retain Resistance Setting ............................. 15 2 I C Interface ..................................................................................... 12 Outline Dimensions ....................................................................... 16 Operation ......................................................................................... 13 Ordering Guide .......................................................................... 16 REVISION HISTORY 5/12Rev. B to Rev. C Changes to Features and General Description Sections .............. 1 Changes to I Parameters, Table 1 ................................................ 3 DD Changes to IDD Parameters, Table 2 ................................................ 4 Changes to Figure 10 ........................................................................ 9 Removed Evaluation Board Section ............................................. 15 Changes to Ordering Guide .......................................................... 16 8/09Rev. A to Rev. B Changes to Power Supply Sensitivity Parameter .......................... 3 Updated Outline Dimensions ........................................................ 16 Changes to Ordering Guide ........................................................... 16 7/05Rev. 0 to Rev. A Changes to Table 1 ............................................................................ 3 Changes to Table 2 ............................................................................ 4 Changes to Absolute Maximum Ratings ....................................... 6 Moved Pin Configuration and Function Descriptions ................ 7 Deleted Table 7 ................................................................................ 12 Changes to Operation Section ....................................................... 13 Deleted Figure 31 ............................................................................. 14 Changes to Figure 30 and Figure 32 ............................................. 14 9/03Revision 0: Initial Version Rev. C Page 2 of 16