2-Channel, 256-Position a Digital Potentiometer AD5207 FEATURES FUNCTIONAL BLOCK DIAGRAM 256-Position, 2-Channel A1 W1 B1 A2 W2 B2 Potentiometer Replacement 10 k , 50 k , 100 k Power Shut-Down, Less than 5 A SHDN 2.7 V to 5.5 V Single Supply 2.7 V Dual Supply RDAC1 REGISTER RDAC2 REGISTER 3-Wire SPI-Compatible Serial Data Input V DD R R Midscale Preset During Power-On V SS APPLICATIONS LOGIC POWER- CS ON Mechanical Potentiometer Replacement RESET 8 AD5207 Stereo Channel Audio Level Control Instrumentation: Gain, Offset Adjustment CLK SDO SERIAL INPUT REGISTER Programmable Voltage-to-Current Conversion SDI Programmable Filters, Delays, Time Constants DGND Line Impedance Matching Automotive Electronics Adjustment The first two bits are address bits. The following eight bits are GENERAL DESCRIPTION the data bits that represent the 256 steps of the resistance value. The AD5207 provides dual channel, 256-position, digitally The reason for two address bits instead of one is to be compatible controlled variable resistor (VR) devices that perform the same with similar products such as AD8402 so that drop-in replacement electronic adjustment function as a potentiometer or variable is possible. The address bit determines the corresponding VR resistor. Each channel of the AD5207 contains a fixed resistor with latch to be loaded with the data bits during the returned positive a wiper contact that taps the fixed resistor value at a point edge of CS strobe. A serial data output pin at the opposite end determined by a digital code loaded into the SPI-compatible of the serial register allows simple daisy chaining in multiple serial-input register. The resistance between the wiper and either VR applications without additional external decoding logic. end point of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. The variable resistor An internal reset block will force the wiper to the midscale posi- offers a completely programmable value of resistance, between tion during every power-up condition. The SHDN pin forces an the A Terminal and the wiper or the B Terminal and the wiper. open circuit on the A Terminal and at the same time shorts the The fixed A-to-B terminal resistance of 10 k , 50 k or 100 k wiper to the B Terminal, achieving a microwatt power shutdown has a 1% channel-to-channel matching tolerance with a nomi- state. When SHDN is returned to logic high, the previous latch nal temperature coefficient of 500 ppm/C. A unique switching settings put the wiper in the same resistance setting prior to circuit minimizes the high glitch inherent in traditional switched shutdown. The digital interface remains active during shutdown resistor designs and avoids any make-before-break or break- code changes can be made to produce new wiper positions when before-make operation. the device is resumed from shutdown. Each VR has its own VR latch, which holds its programmed The AD5207 is available in 1.1 mm thin TSSOP-14 package, resistance value. These VR latches are updated from an internal which is suitable for PCMCIA applications. All parts are guaran- serial-to-parallel shift register, which is loaded from a standard teed to operate over the extended industrial temperature range 3-wire serial-input digital interface. Ten bits, to make up the of 40C to +125C. data word, are required and clocked into the serial input register. REV. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. use, nor for any infringements of patents or other rights of third parties that Tel: 781/329-4700 www.analog.com may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Fax: 781/326-8703 Analog Devices, Inc., 2001AD5207SPECIFICATIONS ELECTRICAL CHARACTERISTICS 10 k , 50 k , 100 k VERSION (V = 5 V, V = 0, V = 5 V, DD SS A V = 0, 40 C < T < +125 C unless otherwise noted.) B A 1 Parameter Symbol Conditions Min Typ Max Unit DC CHARACTERISTICS RHEOSTAT MODE Specifications Apply to All VRs 2 Resistor Differential Nonlinearity R-DNL R , V = NC 1 +1 LSB WB A 2 Resistor Nonlinearity R-INL R , V = NC 1.5 +1.5 LSB WB A 3 Nominal Resistor Tolerance R 30 +30 % Resistance Temperature Coefficient R /TV = V , Wiper = No Connect 500 ppm/C AB AB DD Wiper Resistance R I = 1 V/R, V = 5 V 50 100 W W DD Nominal Resistance Match R/R Ch 1 to 2, V = V , T = 25C 0.2 1 % O AB DD A DC CHARACTERISTICS POTENTIOMETER DIVIDER MODE Specifications Apply to All VRs Resolution N 8 Bits 4 Integral Nonlinearity INL 1.5 +1.5 LSB 4 Differential Nonlinearity DNL V = 5 V, V = 0 V 1 +1 LSB DD SS Voltage Divider Temperature V / T Code = 80 15 ppm/C W H Coefficient Full-Scale Error V Code = FF 1.5 LSB WFSE H Zero-Scale Error V Code = 00 +1.5 LSB WZSE H RESISTOR TERMINALS 5 Voltage Range V V + V 5.5 V V V V A, B, W DD SS SS DD 6 Capacitance A , B C f = 1 MHz, Measured to GND, Code = 80 45 pF X X A,B H 6 Capacitance W C f = 1 MHz, Measured to GND, Code = 80 70 pF X W H 7 Shutdown Current I V = V , V = 0 V, SHDN = 0 5 A A SD A DD B Shutdown Wiper Resistance R V = V , V = 0 V, SHDN = 0, V = 5 V 200 W SD A DD B DD Common-Mode Leakage I V = V = V /2 1 nA CM A B DD DIGITAL INPUTS AND OUTPUTS Input Logic High V V = 5 V, V = 0 V 2.4 V IH DD SS Input Logic Low V V = 5 V, V = 0 V 0.8 V IL DD SS Input Logic High V V = 3 V, V = 0 V 2.1 V IH DD SS Input Logic Low V V = 3 V, V = 0 V 0.6 V IL DD SS Output Logic High V R = 1 k to V V 0.1 V OH L DD DD Output Logic Low V I = 1.6 mA, V = 5 V 0.4 V OL OL DD Input Current I V = 0 V or 5 V 10 A IL IN 6 Input Capacitance C 10 pF IL POWER SUPPLIES Power Single-Supply Range V V = 0 V 2.7 5.5 V DD RANGE SS Power Dual-Supply Range V 2.2 2.7 V DD/SS RANGE Positive Supply Current I V = V or V = GND, V = 0 V 40 A DD IH DD IL SS Negative Supply Current I V = V or V = GND V = 2.5 V 40 A SS IH DD IL SS 8 Power Dissipation P V = 5 V or V = 0 V, V = 5 V 0.2 mW DISS IH IL DD Power Supply Sensitivity, V PSS V = 5 V 10%, V = 0 V, Code = 80 0.01 %/% DD DD SS H Power Supply Sensitivity, V PSS V = 2.5 V 10%, V = 2.5 V, Code = 80 0.03 %/% SS SS DD H 6, 9 DYNAMIC CHARACTERISTICS Bandwidth 3 dB BW 10 k R = 10 k 600 kHz AB Bandwidth 3 dB BW 50 k R = 50 k 125 kHz AB Bandwidth 3 dB BW 100 k R = 100 k 71 kHz AB Total Harmonic Distortion THD V = 1 V rms, V = 0 V, f = 1 kHz, R = 10 k 0.003 % W A B AB V Settling Time t R = 10 k /50 k /100 k , 1 LSB Error Band 2/9/18 s W S AB Resistor Noise Voltage e R = 5 k , f = 1 kHz, RS = 0 9 nVHz N WB WB 10 Crosstalk C V = 5 V, V = 0 V 65 dB T A B 2 REV. 0