1-/2-Channel 15 V Digital Potentiometer AD5260/AD5262 FEATURES FUNCTIONAL BLOCK DIAGRAMS A WB 256 positions AD5260: 1 channel SHDN AD5262: 2 channels (independently programmable) AD5260 Potentiometer replacement V DD RDAC 20 k, 50 k, 200 k REGISTER V SS Low temperature coefficient: 35 ppm/C V 4-wire, SPI-compatible serial data input L POWER-ON PR 5 V to 15 V single-supply 5.5 V dual-supply operation RESET CS LOGIC Power on midscale preset 8 CLK SERIAL INPUT REGISTER SDO APPLICATIONS SDI GND Mechanical potentiometer replacement Instrumentation: gain, offset adjustment Figure 1. AD5260 Stereo channel audio level control A1W1 B1 A2 W2 B2 Programmable voltage-to-current conversion Programmable filters, delays, time constants SHDN Line impedance matching V DD Low resolution DAC replacement RDAC1 RDAC2 REGISTER REGISTER V SS GENERAL DESCRIPTION V L The AD5260/AD5262 provide a single- or dual-channel, 256- POWER-ON PR 1 CS LOGIC position, digitally controlled variable resistor (VR) device. RESET 8 These devices perform the same electronic adjustment function CLK as a potentiometer or variable resistor. Each channel of the SERIAL INPUT REGISTER SDO SDI AD5260/AD5262 contains a fixed resistor with a wiper contact GND AD5262 that taps the fixed resistor value at a point determined by a Figure 2. AD5262 digital code loaded into the SPI-compatible serial-input register. The resistance between the wiper and either end point of the edge of the CLK pin. The AD5262 address bit determines the fixed resistor varies linearly with respect to the digital code corresponding VR latch to be loaded with the last eight bits of transferred into the VR latch. The variable resistor offers a the data word during the positive edging of CS strobe. A serial completely programmable value of resistance, between the A data output pin at the opposite end of the serial register enables terminal and the wiper or the B terminal and the wiper. The simple daisy-chaining in multiple VR applications without fixed A-to-B terminal resistance of 20 , 50 , or 200 has a PR additional external decoding logic. An optional reset pin ( ) nominal temperature coefficient of 35 ppm/C. Unlike the forces the wiper to the midscale position by loading 0x80 into majority of the digital potentiometers in the market, these the VR latch. devices can operate up to 15 V or 5 V provided proper supply The AD5260/AD5262 are available in thin surface-mount voltages are furnished. 14-lead TSSOP and 16-lead TSSOP packages. All parts are Each VR has its own VR latch that holds its programmed guaranteed to operate over the extended industrial temperature resistance value. These VR latches are updated from an internal range of 40C to +85C. serial-to-parallel shift register, which is loaded from a standard 3-wire serial-input digital interface. The AD5260 contains an 1 The terms digital potentiometers, VR, and RDAC are used interchangeably. 8-bit serial register whereas the AD5262 contains a 9-bit serial register. Each bit is clocked into the register on the positive Rev. A 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 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781.461.3113 20022010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 02695-002 02695-001AD5260/AD5262 TABLE OF CONTENTS Features .............................................................................................. 1 Layout and Power Supply Bypassing ....................................... 18 Applications....................................................................................... 1 Terminal Voltage Operating Range ......................................... 18 General Description ......................................................................... 1 Power-Up Sequence ................................................................... 18 Functional Block Diagrams............................................................. 1 RDAC Circuit Simulation Model............................................. 18 Revision History ............................................................................... 2 Macro Model Net List for RDAC ............................................. 18 Specifications..................................................................................... 3 Applications Information .............................................................. 19 Electrical Characteristics20 k, 50 k, 200 k Versions .. 3 Bipolar DC or AC Operation from Dual Supplies................. 19 Timing Diagrams.......................................................................... 5 Gain Control Compensation .................................................... 19 Absolute Maximum Ratings............................................................ 6 Programmable Voltage Reference............................................ 19 ESD Caution.................................................................................. 6 8-Bit Bipolar DAC ...................................................................... 19 Pin Configurations and Function Descriptions ........................... 7 Bipolar Programmable Gain Amplifier................................... 20 Typical Performance Characteristics ............................................. 9 Programmable Voltage Source with Boosted Output ........... 20 Test Circuits..................................................................................... 14 Programmable 4 mA-to-20 mA Current Source ................... 20 Theory of Operation ...................................................................... 15 Programmable Bidirectional Current Source......................... 21 Digital Interfacing ...................................................................... 15 Programmable Low-Pass Filter ................................................ 21 Daisy-Chain Operation ............................................................. 16 Programmable Oscillator .......................................................... 21 RDAC Structure.......................................................................... 16 Resistance Scaling ...................................................................... 22 Programming the Variable Resistor......................................... 16 Outline Dimensions....................................................................... 23 Programming the Potentiometer Divider ............................... 17 Ordering Guide .......................................................................... 24 REVISION HISTORY 8/10Rev. 0 to Rev. A Changes to Figure 11 Caption and Figure 12 ................................9 Updated Format..................................................................Universal Changes to Figure 31...................................................................... 12 Deleted Figure 1 Renumbered Sequentially................................. 1 Changes to Figure 35 Caption ...................................................... 13 Changes to General Description Section ...................................... 1 Changes to Figure 43 and Figure 46............................................. 14 Changes to Conditions of Channel Resistance Matching Deleted Potentiometer Family Selection Guide ......................... 18 (AD5262 only) Parameter, Voltage Divider Temperature Change to Programmable Voltage Source with Boosted Output Coefficient Parameter, Full-Scale Error Parameter, and Zero- Section.............................................................................................. 20 Scale Error Parameter, Table 1 ........................................................ 3 Changes to Figure 64...................................................................... 21 Changes to Table 2 and Table 3....................................................... 5 Updated Outline Dimensions....................................................... 23 Changes to Table 4............................................................................ 6 Changes to Ordering Guide .......................................................... 24 Changes to Table 5............................................................................ 7 Changes to Table 6............................................................................ 8 3/02Revision 0: Initial Version Rev. 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