256-Position SPI Compatible Digital Potentiometer AD5160 FUNCTIONAL BLOCK DIAGRAM FEATURES V DD 256-position End-to-end resistance 5 k, 1 0 k, 50 k, 10 0 k A Compact SOT-23-8 (2.9 mm 3 mm) package CS SPI INTERFACE SPI compatible interface SDI Power-on preset to midscale W CLK Single supply 2.7 V to 5.5 V WIPER Low temperature coefficient 45 ppm/C B REGISTER Low power, IDD = 8 A Wide operating temperature 40C to +125C Evaluation board available GND Figure 1. APPLICATIONS Mechanical potentiometer replacement in new designs Transducer adjustment of pressure, temperature, position, chemical, and optical sensors PIN CONFIGURATION RF amplifier biasing W 1 8 A Automotive electronics adjustment V 2 AD5160 7 B DD Gain control and offset adjustment 3 6 GND CS TOP VIEW (Not to Scale) CLK 4 5 SDI GENERAL OVERVIEW Figure 2. The AD5160 provides a compact 2.9 mm 3 mm packaged solution for 256-position adjustment applications. These devices perform the same electronic adjustment function as mechanical potentiometers or variable resistors, with enhanced resolution, solid-state reliability, and superior low temperature coefficient performance. The wiper settings are controllable through an SPI compatible digital interface. The resistance between the wiper and either end point of the fixed resistor varies linearly with respect to the digital code transferred into the RDAC latch. Operating from a 2.7 V to 5.5 V power supply and consuming less than 5 A allows for usage in portable battery-operated Note: The terms digital potentiometer, VR, and RDAC are used interchangeably. applications. Rev. 0 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 registered trademarks are the property of their respective companies. Fax: 781.326.8703 2003 Analog Devices, Inc. All rights reserved. AD5160 TABLE OF CONTENTS Electrical Characteristics5 k Version ...................................... 3 ESD Protection ........................................................................... 13 Electrical Characteristics10 k, 50 k, 100 k Versions ....... 4 Terminal Voltage Operating Range.......................................... 13 Timing Characteristics5 k, 10 k, 50 k, 100 k Versions 5 Power-Up Sequence ................................................................... 13 Absolute Maximum Ratings ........................................................... 5 Layout and Power Supply Bypassing ....................................... 14 Typical Performance Characteristics ............................................. 6 Pin Configuration and Function Descriptions........................... 15 Test Circuits..................................................................................... 10 Pin Configuration ...................................................................... 15 SPI Interface .................................................................................... 11 Pin Function Descriptions ........................................................ 15 Operation......................................................................................... 12 Outline Dimensions ....................................................................... 16 Programming the Variable Resistor ......................................... 12 Ordering Guide .......................................................................... 16 Programming the Potentiometer Divider ............................... 13 ESD Caution................................................................................ 16 SPI Compatible 3-Wire Serial Bus ........................................... 13 REVISION HISTORY Revision 0: Initial Version Rev. 0 Page 2 of 16