AD5280 Analog Devices, AD5280 Datasheet
AD5280
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AD5280 Summary of contents
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... Wiper position programming defaults to midscale at system power-on. When powered, the VR wiper position is programmed C-compatible, 2-wire serial data interface. The AD5280/ AD5282 feature sleep mode programmability. This allows any level of preset in power-up and is an alternative to a costly EEPROM solution. Both parts have additional programmable ...
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... AD5280/AD5282 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagrams............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Electrical Characteristics............................................................. 3 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6 Typical Performance Characteristics ............................................. 7 Test Circuits..................................................................................... 12 Theory of Operation ...................................................................... 14 Rheostat Operation .................................................................... 14 Potentiometer Operation........................................................... 14 Digital Interface .............................................................................. 16 2-Wire Serial Bus........................................................................ 16 Readback RDAC Value ...
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... kΩ, Code = 0x80 kΩ, Code = 0x80 200 kΩ, Code = 0x80 AB Rev Page AD5280/AD5282 < +85°C, unless otherwise noted Min Typ Max −1 ±1/4 +1 −1 ±1/4 +1 −30 + 150 8 − ...
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... AD5280/AD5282 Parameter Symbol Total Harmonic Distortion THD V Settling Time Crosstalk CT Analog Crosstalk CTA Resistor Noise Voltage e N_WB INTERFACE TIMING CHARACTERISTICS (applies to all parts) SCL Clock Frequency f SCL t Bus Free Time Between t BUF 1 Stop and Start t Hold Time (Repeated t HD:STA 2 Start) ...
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... Table 3. Thermal Resistance −40°C to +85°C Package Type 150°C −65°C to +150°C TSSOP-14 TSSOP-16 260°C ESD CAUTION 20 sec to 40 sec Rev Page AD5280/AD5282 − θ JMAX θ Unit JA 206 °C/W 150 °C/W ...
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... AD5280 B TOP VIEW SHDN 5 6 SCL 7 SDA Figure 4. AD5280 Pin Configuration Table 4. AD5280 Pin Function Descriptions Pin No. Mnemonic Description 1 A Resistor Terminal Wiper Terminal Resistor Terminal Positive Power Supply. Specified for DD operation from (sum ≤ ...
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... R = 20kΩ 25°C A 160 192 224 256 R = 20kΩ AB 160 192 224 256 /V = ± Rev Page AD5280/AD5282 0.5 R 0.4 0.3 0 –40°C A 0.1 0 –0.1 –0.2 –0.3 –0.4 –0 128 160 192 CODE (Decimal) Figure 9. DNL vs. Code ± ...
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... AD5280/AD5282 1.0 AVG +3σ 0.5 AVG AVG –3σ 0 –0.5 –1 – ( Figure 12. INL Over Supply Voltage 2.0 1.5 AVG +3σ 1.0 AVG 0.5 AVG –3σ 0 –0.5 –1.0 –1.5 –2 – ( Figure 13. R-INL Over Supply Voltage 0 –0.2 –0.4 ...
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... 25°C A –6 –12 –18 –24 –30 –36 –42 –48 –54 –60 224 256 0 /ΔT vs. Code, WB Rev Page AD5280/AD5282 80H 40H 20H 10H 08H 04H 02H 01H T = 25° 50mV rms 10k 100k FREQUENCY (Hz) Figure 21. Gain vs. Frequency vs. Code kΩ ...
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... AD5280/AD5282 0 –6 – 50kΩ –18 150kHz – 200kΩ –30 35kHz –36 –42 –48 –54 –60 0 10k FREQUENCY (Hz) Figure 24. −3 dB Bandwidth –6dB R = 200kΩ 100 1k FREQUENCY (Hz) Figure 25. Normalized Gain Flatness vs. Frequency 500 400 300 200 100 0 10k 100k FREQUENCY (Hz) Figure 26 ...
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... AB 0. 128 192 CODE (Decimal) Figure 31. I vs. Code WB_MAX 40 CODES SET TO MIDSCALE 3 LOTS SAMPLE SIZE = 135 Figure 32. Channel-to-Channel Resistance Matching (AD5282) = OPEN B 224 256 Rev Page AD5280/AD5282 LONG TERM CHANNEL-TO-CHANNEL RAB MATCH (%) ...
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... AD5280/AD5282 TEST CIRCUITS Figure 33 to Figure 43 define the test conditions used in the product specification table. DUT 1LSB = V+/ Figure 33. Potentiometer Divider Nonlinearity Error (INL, DNL) NO CONNECT DUT Figure 34. Resistor Position Nonlinearity Error (Rheostat Operation; R-INL, R-DNL ...
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... CM NC Figure 41. Common-Mode Leakage Current V I LOGIC LOGIC SCL SCA DIGITAL INPUT VOLTAGE Figure 42. V Current vs. Digital Input Voltage LOGIC V N Figure 43. Analog Crosstalk (AD5282 Only) Rev Page AD5280/AD5282 RDAC RDAC OUT ...
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... B starting LSB less than 5 V. Each LSB of voltage is equal to the voltage applied across divided by the 256 positions of the potentiometer divider. Because the AD5280/AD5282 can be supplied by dual supplies, the general equation defining the output voltage at V Rev ...
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... Instruction Byte Rev Page AD5280/AD5282 and R and not on the absolute ACK. BY AD5280/AD5282 FRAME 3 DATA BYTE ACK. BY MASTER FRAME 2 STOP BY MASTER Data Byte D0 ACK. BY AD5280/5282 STOP BY MASTER ...
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... The RDACs are connected to this bus as slave devices. As shown in Figure 45, Figure 46, and Table 6, the first byte of the AD5280/AD5282 is a slave address byte. It has a 7-bit slave address and bit. The 5 MSBs are 01011, and the two bits that follow are deter- mined by the state of the AD0 pin and the AD1 pin of the device ...
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... As shown in Figure 44, when shutdown is asserted, the AD5280/AD5282 open SW to let the A terminal float and A short the W terminal to the B terminal. The AD5280/AD5282 consume negligible power during shutdown mode, resuming the previous setting once the SHDN pin is released. In addition, shutdown can be implemented with the device digital output as shown in Figure 47 ...
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... These applications are sometimes operated between ground and a negative supply voltage such that the systems can be biased at ground to avoid large bypass capacitors that may significantly impede the ac performance. Like most digital potentiometers, the AD5280/AD5282 can be configured with a negative supply (see Figure 50 ...
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... Figure 54). Notice that the digital ground should also be joined remotely to the analog ground at one point to minimize digital ground bounce 10µF 0.1µ 10µF 0.1µ Figure 54. Power Supply Bypassing Rev Page AD5280/AD5282 V DD AD5280/ AD5282 V GND SS ...
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... A 2 significant and the compensation can be avoided in most cases 8-BIT I 2 –5.0V R ADR512 A AD5280/AD5282 can be configured as a high voltage DAC high The output is Rev Page DAC BIAS U1A ...
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... where K is the ratio set by U WB1 WA1 +15V As in the previous example, in the simpler and more common case where single digital AD5280 potentiometer is + used. U OP2177 V O – V and − relationship becomes –15V – ...
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... PROGRAMMABLE BIDIRECTIONAL CURRENT SOURCE 102Ω AD5280 100Ω L For applications that require bidirectional current control or higher voltage compliance, a Howland current pump can be a solution (see Figure 62) ...
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... R2 converges. R2 increase the amplitude, but the total resistance cannot be too large to prevent saturation of the output. +2. V– –2. //( (14) (15) Rev Page AD5280/AD5282 because and V are interdependent variables. With proper ...
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... RDAC CIRCUIT SIMULATION MODEL The internal parasitic capacitances and the external capacitive loads dominate the ac characteristics of the RDACs. Configured as a potentiometer divider, the −3 dB bandwidth of the AD5280 (20 kΩ resistor) measures 310 kHz at half scale. Figure 24 provides the Bode plot characteristics of the three available resistor versions: 20 kΩ ...
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... Figure 66. 14-Lead Thin Shrink Small Outline Package (TSSOP) (RU-14) Dimensions shown in millimeters 5.10 5.00 4. 4.50 6.40 4.40 BSC 4. PIN 1 1.20 MAX 0.20 0.09 8° 0.30 0.65 0° 0.19 SEATING BSC PLANE COPLANARITY 0.10 COMPLIANT TO JEDEC STANDARDS MO-153-AB Figure 67. 16-Lead Thin Shrink Small Outline Package (TSSOP) (RU-16) Dimensions shown in millimeters Rev Page AD5280/AD5282 0.75 8° 0.60 0° 0.45 0.75 0.60 0.45 ...
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... AD5280/AD5282 ORDERING GUIDE No Model Channels AD5280BRU20 1 AD5280BRU20-REEL7 1 AD5280BRU50 1 AD5280BRU50-REEL7 1 AD5280BRU200 1 AD5280BRU200-REEL7 1 2 AD5280BRUZ20 1 2 AD5280BRUZ20-REEL7 1 2 AD5280BRUZ50 1 2 AD5280BRUZ50-REEL7 1 AD5280BRUZ200 AD5280BRUZ200-R7 1 AD5282BRU20 2 AD5282BRU20-REEL7 2 AD5282BRU50 2 AD5282BRU50-REEL7 2 AD5282BRU200 2 AD5282BRU200-REEL7 2 2 AD5282BRUZ20 2 2 AD5282BRUZ20-REEL7 2 2 AD5282BRUZ50 2 2 AD5282BRUZ50-REEL7 2 2 AD5282BRUZ200 2 AD5282BRUZ200- AD5282-EVAL ...
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... NOTES Rev Page AD5280/AD5282 ...
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... AD5280/AD5282 NOTES ©2002–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C02929-0-8/07(B) Rev Page ...