AS1500/AS1501/AS1502/AS1503 D a ta S he e t D i g i ta l P o t e n t i o m e t e r 1 General Description 2 Key Features 256 - Taps The AS1500 is a digital potentiometer with 256 programmable steps. The values of the resistor can be controlled via 3 wire serial interface capable to handle programming rates up to 10MHz. Available in four Resistance values - AS1500 resistance 10kΩ - AS1501 resistance 20kΩ - AS1502 resistance 50kΩ - AS1503 resistance 100kΩ Standby current - Less than 1 µA The AS1500 is available in four different resistor values. The AS1500 incorporates a 10kΩ, the AS1501 a 20kΩ, the AS1502 a 50kΩ and the AS1503 a 100kΩ fixed resistor. The wiper contact taps the fixed resistor at points determined by the 8-bit digital code word. The resistance between the wiper and the endpoint of the resistor is linear. The switching action is performed in a way that no glitches occur. 3-Wire Serial Data Interface 10 MHz Update Data Loading Rate 2.7 V to 5.5 V Single-Supply Operation Temperature Range –40º to +125º The AS150x is available in an 8-pin SOIC package. All parts are guaranteed to operate over the extended industrial temperature range of –40º to +125º. 8-pin SOIC Package 3 Applications The AS1500 is ideal for volume controls in TV sets and audio systems, and applications that require line impedance matching, programmable filters or power supply adjustment. The AS1500 can also be designed in as a replacement for mechanical potentiometers. Figure 1. Application Diagram VCC A SDI CK CSN 10 Bit Serial Latch 8 8-Bit Latch 8 W B GND www.austriamicrosystems.com Revision 1.01 1 - 14 AS1500 Data Sheet - Pin Assignments 4 Pin Assignments Figure 2. Pin Assignments (Top View) B 1 8 A GND 2 7 W AS1500 CSN 3 6 VCC SDI 4 5 CK Pin Descriptions Table 1. Pin Description Pin Name Pin Number B 1 Terminal B RDAC GND 2 Ground CSN 3 Chip Select Input, Active Low. When CSN returns high, data in the serial input register is loaded into the DAC register. SDI 4 Serial Data Input CK 5 Serial Clock Input, Positive Edge Triggered. VCC 6 Positive power supply, specified for operation at both 3V and 5V. W 7 Wiper RDAC A 8 Terminal A RDAC www.austriamicrosystems.com Description Revision 1.01 2 - 14 AS1500 Data Sheet - Absolute Maximum Ratings 5 Absolute Maximum Ratings (TA = 25º C, unless otherwise noted) Table 2. Absolute Maximum Ratings Parameter Min Max Units VCC to GND -0.3 +7 V VA, VB, VW to GND 0 VCC V AX – BX, AX – WX, BX – WX ±20 mA Digital Input and Output Voltage to GND 0 +7 V Operating Temperature Range -40 +125 ºC +150 ºC +150 ºC Maximum Junction Temperature (TJ max) Storage Temperature Package body temperature -65 +260 ºC www.austriamicrosystems.com The reflow peak soldering temperature (body temperature) specified is in accordance with IPC/JEDEC J-STD020C “Moisture/Reflow Sensitivity Classification for Non-Hermetic Solid State Surface Mount Devices”. The lead finish for Pb-free leaded packages is matte tin (100% Sn). (TJ max - TA) / θJA Package Power Dissipation ESD Notes 1 Revision 1.01 kV HBM MIL-Std883E 3015.7methods. 3 - 14 AS1500 Data Sheet - Electrical Characteristics 6 Electrical Characteristics AS1500 / AS1501 – SPECIFICATIONS VCC = 3V±10% or 5V±10%, VA = VCC, VB = 0V, –40ºC ≤ TA ≤ +125ºC unless otherwise noted. Table 3. Electrical Characteristics – 10k and 20k Versions Symbol Parameter Conditions 1 Min Typ Max Units TA = 25ºC, VCC = 5V, AS1500, Version: 50kΩ 8 10 12 kΩ TA = 25ºC, VCC = 5V, AS1501, Version: 100kΩ 16 20 24 kΩ DC Characteristics Rheostat Mode RAB 2 Nominal Resistance ΔRAB/ΔT Resistance Tempco VAB = VCC, Wiper = No Connect RW Wiper Resistance VCC = 5V 20 100 200 Ω R-DNL Resistor Differential NL RWB, VCC = 5V, VA = No Connect -1 ±1/4 +1 LSB R-INL Resistor Integral NL RWB, VCC = 5V, VA = No Connect -2 ±1/2 +2 LSB 3 4 500 ppm/ºC DC Characteristics Potentiometer Divider N Resolution INL Integral Nonlinearity DNL 8 Differential Nonlinearity Bits VCC = 5.5V TA = 25ºC -2 ±1/2 +2 LSB VCC = 2.7V TA = 25ºC -2 ±1/2 +2 LSB VCC = 5.5V TA = 25ºC -1 ±1/4 +1 LSB VCC = 2.7V TA = 25ºC -1 ±1/4 +1 LSB ΔVW /ΔT Voltage Divider Tempco Code = 80H VWFSE Full-Scale Error Code = FFH, VCC = 5.5V -4 -2.8 0 LSB VWFSE Zero-Scale Error Code = 00H, VCC = 5.5V 0 1.3 2 LSB VCC V 15 ppm/ºC Resistor Terminals 5 VA, B, W Voltage Range CA, B Capacitance Ax, Bx f =1MHz, Measured to GND, Code = 80H 75 pF CW Capacitance Wx f =1MHz, Measured to GND, Code = 80H 120 pF 0 6 Digital Inputs and Outputs VIH Input Logic High VCC = 5V VIL Input Logic Low VCC = 5V VIH Input Logic High VCC = 3V VIL Input Logic Low VCC = 3V 0.6 V IIH, IIL Input Current VIN = 5V or 0V, VCC = 5V ±1 µA CIL Input Capacitance 2.4 V 0.8 2.1 V V 5 pF Power Supplies VCC Power Supply Range IDD Supply Current (CMOS) VIH = VCC or VIL = 0V, VCC = 5.5V IDD Supply Current (TTL) www.austriamicrosystems.com 7 2.7 VIH = 2.4V or 0.8V, VCC = 5.5V Revision 1.01 5.5 V 0.1 1 µA 0.9 4 mA 4 - 14 AS1500 Data Sheet - Electrical Characteristics Table 3. Electrical Characteristics – 10k and 20k Versions Symbol PDISS PSSR Parameter Power Dissipation BW_20k THDW VCC = 5V+0.5VP sine wave @ 1kHz Power Supply Suppression Ratio Max Units 27.5 µW AS1500, Version: 10kΩ -54 -25 dB AS1501, Version: 20kΩ -52 -25 dB Bandwidth –3dB Bandwidth –3dB RWB = 10kΩ, VCC = 5V 1000 kHz RWB = 20kΩ, VCC = 5V 500 kHz Total Harmonic Distortion VA = 1VRMS + 2VDC, VB = 2VDC, f = 1kHz 0.003 % RWB = 5kΩ, VA = VCC, VB = 0V, ±1% Error Band 2 RWB = 10kΩ, VA = VCC, VB = 0V, ±1% Error Band 4 µs RWB = 5kΩ, f =1kHz 9 nV/ √ Hz RWB = 10kΩ, f =1kHz 13 nV/ √ Hz VW Settling Time tS_20k eNWB_20k 1 Typ 9 tS_10k eNWB_10k Min VIH = VCC or VIL = 0V, VCC = 5.5V 8 (CMOS) Dynamic Characteristics BW_10k Conditions Resistor Noise Voltage µs 1. 2. 3. 4. 5. 6. Typicals represent average readings at 25ºC and VCC = 5V. Wiper is not connected. IAB = 350µA for the 10kΩ version and 175µA for the 20kΩ version. All Tempcos are guaranteed by design and not subject to production test. Terminal A is not connected. IW = 350µA for the 10kΩ version and 175µA for the 20kΩ version. Resistor terminals A, B, W have no limitations on polarity with respect to each other. All capacitances are guaranteed by design and not subject to production test. Resistor-terminal capacitance tests are measured with 2.5V bias on the measured terminal. The remaining resistor terminals are left open circuit. 7. Worst-case supply current consumed when input logic level at 2.4V, standard characteristic of CMOS logic. 8. PDISS is calculated from (IDD×VCC). CMOS logic level inputs result in minimum power dissipation. 9. All dynamic characteristics are guaranteed by design and not subject to production test. All dynamic characteristics use VCC=5V. AS1502 / AS1503 – SPECIFICATIONS VCC = 3V±10% or 5V±10%, VA = VCC, VB = 0V, –40ºC ≤ TA ≤ +125ºC unless otherwise noted. Table 4. Electrical Characteristics – 50k and 100k Versions Symbol Parameter Conditions 1 Min Typ Max Units TA = 25ºC, VCC = 5V, AS1502, Version: 50kΩ 40 50 60 kΩ TA = 25ºC, VCC = 5V, AS1503, Version: 100kΩ 80 100 120 kΩ DC Characteristics Rheostat Mode RAB 2 Nominal Resistance ΔRAB/ΔT Resistance Tempco VAB = VCC, Wiper = No Connect RW Wiper Resistance VCC = 5V 20 100 200 Ω R-DNL Resistor Differential NL RWB, VCC = 5V, VA = No Connect -1 ±1/4 +1 LSB R-INL Resistor Integral NL RWB, VCC = 5V, VA = No Connect -2 ±1/2 +2 LSB 3 4 www.austriamicrosystems.com Revision 1.01 500 ppm/ºC 5 - 14 AS1500 Data Sheet - Electrical Characteristics Table 4. Electrical Characteristics – 50k and 100k Versions Symbol Parameter Conditions Min 1 Typ Max Units DC Characteristics Potentiometer Divider N INL DNL ΔVW /ΔT VWFSE VWFSE Resolution 8 Integral Nonlinearity Differential Nonlinearity Bits VCC = 5.5V TA = 25ºC -4 ±1 +4 LSB VCC = 2.7V TA = 25ºC -4 ±1 +4 LSB VCC = 5.5V TA = 25ºC -1 ±1/4 +1 LSB VCC = 2.7V TA = 25ºC -1 ±1/4 +1 LSB Voltage Divider Tempco Code = 80H Full-Scale Error Code = FFH, VCC= 5.5V -1 -0.25 0 LSB Zero-Scale Error Code = 00H, VCC = 5.5V 0 0.1 1 LSB VCC V 15 ppm/ºC Resistor Terminals 5 VA, B, W Voltage Range CA, B Capacitance Ax, Bx f =1MHz, Measured to GND, Code = 80H 15 pF CW Capacitance Wx f =1MHz, Measured to GND, Code = 80H 80 pF 0 6 Digital Inputs and Outputs VIH Input Logic High VCC = 5V VIL Input Logic Low VCC = 5V VIH Input Logic High VCC = 3V VIL Input Logic Low VCC = 3V 0.6 V IIH, IIL Input Current VIN = 5V or 0V, VCC = 5V ±1 µA CIL Input Capacitance 2.4 V 0.8 2.1 V V 5 pF Power Supplies VCC Power Supply Range IDD Supply Current (CMOS) VIH = VCC or VIL = 0V, VCC = 5.5V IDD PDISS PSSR 7 Supply Current (TTL) Power Dissipation 8 (CMOS) Power Supply Suppression Ratio Dynamic Characteristics BW_50k BW_100k THDW 2.7 VIH = 2.4V or 0.8V, VCC = 5.5V 5.5 V 0.1 1 µA 0.9 4 mA 27.5 µW VIH = VCC or VIL = 0V, VCC = 5.5V VCC = 5V+0.5VP sine wave @ 1kHz AS1502, Version: 50kΩ -43 dB AS1503, Version: 100kΩ -52 dB 9 Bandwidth –3dB Bandwidth –3dB RWB = 50kΩ, VCC = 5V 220 kHz RWB = 100kΩ, VCC = 5V 110 kHz Total Harmonic Distortion VA = 1VRMS + 2VDC, VB = 2VDC, f = 1kHz 0.003 % www.austriamicrosystems.com Revision 1.01 6 - 14 AS1500 Data Sheet - Electrical Characteristics Table 4. Electrical Characteristics – 50k and 100k Versions Symbol Parameter tS_50k VW Settling Time tS_100k eNWB_50k eNWB_100k Resistor Noise Voltage Conditions Min 1 Typ Max Units RWB = 50kΩ, VA = VCC, VB = 0V, ±1% Error Band 9 RWB = 100kΩ, VA = VCC, VB = 0V, ±1% Error Band 18 µs RWB = 50kΩ, f =1kHz 20 nV/ √ Hz RWB = 100kΩ, f =1kHz 29 nV/ √ Hz µs 1. 2. 3. 4. 5. 6. Typicals represent average readings at 25ºC and VCC = 5V. Wiper is not connected. IAB = 70µA for the 50kΩ version and 35µA for the 100kΩ version. All Tempcos are guaranteed by design and not subject to production test. Terminal A is not connected. IW = 70µA for the 50kΩ version and 35µA for the 100kΩ version. Resistor terminals A, B, W have no limitations on polarity with respect to each other. All capacitances are guaranteed by design and not subject to production test. Resistor-terminal capacitance tests are measured with 2.5V bias on the measured terminal. The remaining resistor terminals are left open circuit. 7. Worst-case supply current consumed when input logic level at 2.4V, standard characteristic of CMOS logic. 8. PDISS is calculated from (IDD×VCC). CMOS logic level inputs result in minimum power dissipation. 9. All dynamic characteristics are guaranteed by design and not subject to production test. All dynamic characteristics use VCC=5V. AS150x – SPECIFICATIONS VCC = 3V±10% or 5V±10%, VA = VCC, VB = 0V, –40ºC ≤ TA ≤ +125ºC unless otherwise noted. Table 5. Switching Characteristics Symbol Parameter Switching Characteristics 1 Conditions Min Clock Level High or Low 50 ns Typ Max Unit 23 tCH, tCL Input Clock Pulsewidth tDS Data Setup Time 5 ns tDH Data Hold Time 5 ns tCSS CSN Setup Time 10 ns tCSWH CSN High Pulsewidth 10 ns tCSWL CSN Low Pulsewidth tCSH CK Fall to CSN Rise Hold Time 0 ns tCS1 CSN Rise to Clock Rise Setup 10 ns 100 ms 1. Typicals represent average readings at 25ºC and VCC=5V. 2. Guaranteed by design and not subject to production test. Resistor-terminal capacitance tests are measured with 2.5V bias on the measured terminal. The remaining resistor terminals are left open circuit. 3. See timing diagram for location of measured values. All input control voltages are specified with tR = tF = 1ns (10% to 90% of VCC) and timed from a voltage level of 1.6V. Switching characteristics are measured using VCC=3V or 5V. To avoid false clocking, a minimum input logic slew rate of 1V/µs should be maintained. www.austriamicrosystems.com Revision 1.01 7 - 14 AS1500 Data Sheet - Detailed Description 7 Detailed Description Serial-Programming Programming of the AS150x is done via the 3 wire serial interface. The three input signals are serial data input (SDI), clock(CK) and chip select (CSN). A programming sequence consists of 10-bit, where the last eight bit contain the code word for the resistor value. The first two bits A1 and A0 have to be low to program the resistor value (see Table 6). Otherwise the resistor value is not affected. The data is shifted into the internal 10 Bit register with the rising edge of the CK signal. With the rising edge of the CSN signal the data become valid and the resistance is updated (see Figure 3). A detailed block diagram is shown in Figure 4. Table 6. Serial data format (10 bits) A1 A0 0 0 D7 D6 D5 D4 D3 MSB D2 Data D1 D0 LSB Figure 3. Timing Diagram 1 SDI A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 0 CK 1 0 DAC Register Load 1 CSN 0 VCC VOUT 0V Figure 4. Detailed Timing Diagram 1 SDI Ax or Dx Ax or Dx 0 tD tD tCH tCS1 1 CK 0 tCL 1 CSN tCSH tCSS tCSWL tCSWH 0 tS VCC VOUT ± 1% Error Band 0V www.austriamicrosystems.com Revision 1.01 8 - 14 AS1500 Data Sheet - Detailed Description Rheostat Operation The digital potentiometer family AS150x offers nominal resistor values of 10kΩ, 20kΩ, 50kΩ and 100kΩ. The resistor has 256 contact points where the wiper can access the resistor. The 8-bit code word determines the position of the wiper and is decoded through an internal logic. The lowest code 00h is related to the terminal B. The resistance is then only determined by the wiper resistance (100Ω). The resistance for the next code 01h is the nominal resistor RAB (10kΩ, 20kΩ, 50kΩ or 100kΩ) divided through 256 plus the wiper resistor. In case of AS1501 (10kΩ) the total resistance is 39Ω+100Ω=139Ω. Accordingly the resistor for code 02h is 78Ω+100Ω=178Ω. The last code 255h does not connect to terminal A directly (see Figure 5). So the maximum value is 10000Ω - 39Ω +100Ω = 10061Ω. The general formula for the calculation of the resistance RWB is: RWB (Dx)= (Dx)/256 • RAB + RW (EQ 1) where RAB is the nominal resistance between terminal A and B, RW is the wiper resistance and DX is the 8-Bit Code word. In Table 7 the resistor values between the wiper and terminal B for AS1500 are given for specific codes DX. In the zero-scale condition the wiper resistance of 100Ω remains present. Table 7. RDAC-Codes WB DX (Dec) RWB (Ω) Output State 255 10061 Full Scale 128 5100 Midscale 1 139 1 LSB 0 100 Zero-Scale (Wiper Contact Resistance) The maximum current through the wiper and terminal B is 5mA. If the current exceeds this limit the internal switches can degrade or even be damaged. As a mechanical potentiometer the resistances RWA and RWB are totally symmetrical. The relation between them is shown in Figure 5. Figure 5. RWA and RWB versa code RWA, RWB - % of Nominal RAB 10 RWB RWA 75 50 25 0 0 64 12 19 25 CODE - Decimal www.austriamicrosystems.com Revision 1.01 9 - 14 AS1500 Data Sheet - Detailed Description The resistance RWA is the complimentary resistor to RWB and can be controlled digitally as well. RWA starts at the maximum value of the nominal resistance and is reduced with increasing 8-Bit code words. The formula to calculate RWA is given below: RWA (Dx)= (256 - Dx)/256 • RAB + RW (EQ 2) where RAB is the nominal resistance between terminal A and B, RW is the wiper resistance and Dx is the 8-Bit Code word. In Table 8 the resistor values between the wiper and terminal B for AS1500 are given for specific codes Dx. Table 8. RDAC-Codes WA DX (Dec) RWA (Ω) Output State 255 89 Full Scale 128 5050 Midscale 1 10011 1 LSB 0 10050 Zero-Scale Figure 6. Equivalent RDAC Circuit A Rs D7 Rs D6 D5 Rs D4 D3 D2 W D1 D0 RDAC LATCH AND DECODE Rs Rs=RNOMINAL/256 B Voltage Output Operation The AS150x family can easily used in an voltage output mode, where the output voltage is proportional to an applied voltage to a given terminal. When 5V are applied to terminal A and B is set to ground the ouput voltage at the wiper starts at zero volts up to 1LSB less then 5V. One LSB of voltage corresponds to the voltage applied at terminal AB divided through 256 steps of possible wiper settings. The formula is given by VW (Dx)= (Dx)/256 • VAB + VB (EQ 3) where VAB is the voltage applied between terminal A and B, VW is the voltage at the wiper, Dx is the 8-Bit Code word and VB is the voltage at terminal B. The temperature drift is significant better than in Rheostat mode, since the temperature coefficient is determined by the internal resistor ratio. Therefore the temperature drift is only 15ppm/°C. www.austriamicrosystems.com Revision 1.01 10 - 14 AS1500 Data Sheet - Detailed Description Applications The digital potentiometer can replace in many applications the analog trimming potentiometer. The digital potentiometer is not sensitive to vibrations and shocks. It has an extremely small form-factor and can be adjusted very fast (e.g. AS1500 has an update rate of 600kHz). Furthermore the temperature drift, resolution and noise are significant better and cannot be achieved with a mechanical trimming potentiometer. Due to the programmability the resistor settings can be stored in the system memory, so that after a power down the exact settings can be recalled easily. All analog signals must remain within 0 to VCC range. For standard potentiometer applications the wiper output can be used directly. In the case of a low impedance load, a buffer shall be used. www.austriamicrosystems.com Revision 1.01 11 - 14 AS1500 Data Sheet - Package Drawings and Markings 8 Package Drawings and Markings Figure 7. 8-pin SOIC Package Notes: 1. Lead coplanarity should be 0 to 0.10mm (.004”) max. 2. Package surface finishing: (2.1) Top: matte (charmilles #18-30). (2.2) All sides: matte (charmilles #18-30). (2.3) Bottom: smooth or matte (charmilles #18-30). 3. All dimensions exclusive of mold flash, and end flash from the package body shall not exceed 0.24mm (0.10”) per side (D). 4. Details of pin #1 identifier are optional but must be located within the zone indicated. Symbol Min Max A1 B C D E e H h L A 0.10 0.36 0.19 4.80 3.81 0.25 0.46 0.25 4.98 3.99 ZD A2 www.austriamicrosystems.com Revision 1.01 1.27BSC 5.80 0.25 .041 1.52 0º 6.20 0.50 1.27 1.72 8º 0.53REF 1.37 1.57 12 - 14 AS1500 Data Sheet - Ordering Information 9 Ordering Information Table 9. Model Resistor Delivery Form Package Description AS1500 10kΩ Tubes 8-pin SOIC 8-bit Digital Potentiometer AS1501 20kΩ Tubes 8-pin SOIC 8-bit Digital Potentiometer AS1502 50kΩ Tubes 8-pin SOIC 8-bit Digital Potentiometer AS1503 100kΩ Tubes 8-pin SOIC 8-bit Digital Potentiometer AS1500-T 10kΩ T&R 8-pin SOIC 8-bit Digital Potentiometer AS1501-T 20kΩ T&R 8-pin SOIC 8-bit Digital Potentiometer AS1502-T 50kΩ T&R 8-pin SOIC 8-bit Digital Potentiometer AS1503-T 100kΩ T&R 8-pin SOIC 8-bit Digital Potentiometer www.austriamicrosystems.com Revision 1.01 13 - 14 AS1500 Data Sheet - Ordering Information Copyrights Copyright © 1997-2008, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. Disclaimer Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard production flow, such as test flow or test location. The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However, austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems AG rendering of technical or other services. Contact Information Headquarters austriamicrosystems AG A-8141 Schloss Premstaetten, Austria Tel: +43 (0) 3136 500 0 Fax: +43 (0) 3136 525 01 For Sales Offices, Distributors and Representatives, please visit: http://www.austriamicrosystems.com/contact-us www.austriamicrosystems.com Revision 1.01 14 - 14