AD8571 Analog Devices, AD8571 Datasheet
AD8571
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AD8571 Summary of contents
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... Thermocouple amplifiers GENERAL DESCRIPTION This family of amplifiers has ultralow offset, drift, and bias current. The AD8571, AD8572, and AD8574 are single, dual, and quad amplifiers, respectively, featuring rail-to-rail input and output swings. All are guaranteed to operate from 2 single supply. ...
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... AD8571/AD8572/AD8574 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Pin Configurations ........................................................................... 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... Electrical Characteristics...................................................... 3 2.7 V Electrical Characteristics................................................... 4 Absolute Maximum Ratings............................................................ 5 Thermal Characteristics .............................................................. 5 ESD Caution.................................................................................. 5 Typical Performance Characteristics ............................................. 6 Functional Description .................................................................. 14 Amplifier Architecture .............................................................. 14 Basic Auto-Zero Amplifier Theory.......................................... 14 Auto-Zero Phase......................................................................... 14 Amplification Phase ................................................................... 15 High Gain, CMRR, and PSRR .................................................. 16 Maximizing Performance Through Proper Layout ...
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... −40°C ≤ T ≤ +125° kΩ L GBP e p kHz Rev Page AD8571/AD8572/AD8574 Min Typ Max Unit 1 5 μV 10 μ 1.0 1.5 nA 160 300 pA 2 ...
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... Table 2. Parameter INPUT CHARACTERISTICS Offset Voltage Input Bias Current AD8571/AD8574 AD8572 Input Offset Current AD8571/AD8574 AD8572 Input Voltage Range Common-Mode Rejection Ratio 1 Large Signal Voltage Gain Offset Voltage Drift OUTPUT CHARACTERISTICS Output Voltage High Output Voltage Low Short-Circuit Limit Output Current ...
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... SOIC and 300°C TSSOP packages. Table 4. Thermal Resistance Package Type 8-Lead MSOP (RM) 8-Lead TSSOP (RU) 8-Lead SOIC (R) 14-Lead TSSOP (RU) 14-Lead SOIC (R) ESD CAUTION Rev Page AD8571/AD8572/AD8574 is JA θ θ Unit JA JC 190 44 °C/W 240 43 ° ...
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... AD8571/AD8572/AD8574 TYPICAL PERFORMANCE CHARACTERISTICS 180 160 140 120 100 –2.5 –1.5 –0.5 0.5 OFFSET VOLTAGE (µV) Figure 7. Input Offset Voltage Distribution at 2 –40°C, +25°C, +85° –10 –20 – INPUT COMMON-MODE VOLTAGE (V) Figure 8. Input Bias Current vs. Input Common-Mode Voltage ...
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... 2. –10 –20 –30 –40 100 125 150 10k Figure 18. Open-Loop Gain and Phase Shift vs. Frequency Rev Page AD8571/AD8572/AD8574 T = 25° SUPPLY VOLTAGE (V) Figure 16. Supply Current vs. Supply Voltage = 2. 0pF L ∞ 100k 1M 10M ...
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... AD8571/AD8572/AD8574 –100 – –10 –20 –30 –40 100 1k 10k 100k FREQUENCY (Hz) Figure 19. Closed-Loop Gain vs. Frequency at 2 –100 – –10 –20 –30 –40 100 1k 10k 100k FREQUENCY (Hz) Figure 20 ...
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... IN (RET TO GND 0pF 10kΩ –100 OUT 20µs BOTTOM SCALE: 1V/DIV 10k TOP SCALE: 200mV/DIV Figure 30. Negative Overvoltage Recovery Rev Page AD8571/AD8572/AD8574 +OS –OS 100 1k 10k CAPACITANCE (pF ±2. –200mV p-p IN (RET TO GND 0pF 10kΩ – ...
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... AD8571/AD8572/AD8574 V = ±2. 2kΩ –100 60mV p-p IN 200µs Figure 31. No Phase Reversal 140 V = 2.7V S 120 100 100 1k 10k 100k FREQUENCY (Hz) Figure 32. CMRR vs. Frequency at 2.7 V 140 120 100 100 1k 10k 100k FREQUENCY (Hz) Figure 33. CMRR vs. Frequency ...
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... Figure 41. Voltage Noise Density at 2.7 V from kHz 182 156 130 104 Figure 42. Voltage Noise Density from 2.5 kHz Rev Page AD8571/AD8572/AD8574 0Ω S 0.5 1.0 1.5 2.0 2.5 FREQUENCY (kHz 2. 0Ω ...
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... AD8571/AD8572/AD8574 112 FREQUENCY (kHz) Figure 43. Voltage Noise Density from kHz 210 180 150 120 FREQUENCY (kHz) Figure 44. Voltage Noise Density from 150 0Ω S 145 140 135 ...
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... I SC 100 125 150 –75 Figure 49. Output Voltage to Supply Rail vs. Temperature = 100kΩ 100 125 150 Rev Page AD8571/AD8572/AD8574 1kΩ 10kΩ 100kΩ L –50 – 100 125 TEMPERATURE (° ...
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... AD8571/AD8572/AD8574 FUNCTIONAL DESCRIPTION The AD8571/AD8572/AD8574 are CMOS amplifiers that achieve their high degree of precision through random frequency auto-zero stabilization. The autocorrection topology allows the AD857x to maintain its low offset voltage over a wide temperature range, and the randomized auto-zero clock eliminates any intermodulation distortion (IMD) errors at the amplifier output ...
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... ⎢ ⎥ the open-loop gain of an amplifier OSA S ⎣ ⎦ (5) OS, EFF + Putting Equation 12 into the form of Equation 11 gives Rev Page AD8571/AD8572/AD8574 time invariant, and Equation − OSA ...
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... ≠ TS1 + SC1 Figure 54. Mismatch in Seebeck Voltages Causes a Thermoelectric Voltage Error AD8571/AD8572 AD8574 /R1 SHOULD BE PLACED IN CLOSE PROXIMITY AND S ALIGNMENT BALANCE SEEBECK VOLTAGES Figure 55. Using Dummy Components to Cancel Thermoelectric Voltage Errors ...
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... IMD products in the spectrum. The signal-to- noise ratio (SNR) of the output signal is better than 60 dB, or 0.1%. –100 –120 Figure 58. Spectral Analysis of AD8572 in High Gain with an Input Signal 0dB Rev Page AD8571/AD8572/AD8574 0 –20 –40 –60 – FREQUENCY (kHz) 0 – ...
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... AD8571/AD8572/AD8574 BROADBAND AND EXTERNAL RESISTOR NOISE CONSIDERATIONS The total broadband noise output from any amplifier is primarily a function of three types of noise: input voltage noise from the amplifier, input current noise from the amplifier, and Johnson noise from the external resistors used around the amplifier ...
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... Rev Page AD8571/AD8572/AD8574 includes stray capacitances and can differ substantially Rx (Ω) Cx 200 0.47 μ μF Figure 62 shows 5µs 1V Figure 61. AD857x Output Behavior on Power- 100kΩ V AD8571/ 100kΩ AD8572/ AD8574 Figure 62. AD857x Test Circuit for Turn-On Time OUT ...
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... Figure 65, should be used. The value of this trimming resistor should be equal to the value of R multiplied by its tolerance. For example, using 10 kΩ resistors with 1% tolerance would require a series trimming resistor equal to 100 Ω. Rev Page AD8571/ V1 AD8572/ R4 AD8574 ...
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... HIGH ACCURACY THERMOCOUPLE AMPLIFIER Figure 66 shows a K-type thermocouple amplifier configuration with cold-junction compensation. Even from supply, the AD8571 can provide enough accuracy to achieve a resolution of better than 0.02°C from 0°C to 500° used as a tempera- ture measuring device to correct the cold-junction error from the thermocouple and should be placed as close as possible to the two terminating junctions ...
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... AD8571/AD8572/AD8574 OUTLINE DIMENSIONS 3.20 3.00 2.80 5. 3.20 4.90 3.00 4.65 2. PIN 1 0.65 BSC 0.95 0.85 1.10 MAX 0.75 0.15 0.38 0.23 0.00 0.22 0.08 COPLANARITY SEATING 0.10 PLANE COMPLIANT TO JEDEC STANDARDS MO-187-AA Figure 69. 8-Lead Mini Small Outline Package [MSOP] (RM-8) Dimensions shown in millimeters 5.00 (0.1968) 4.80 (0.1890 6.20 (0.2441) 4.00 (0.1574) 1 5.80 (0.2284) 3.80 (0.1497) 4 1.27 (0.0500) BSC 1.75 (0.0688) 1.35 (0.0532) 0.25 (0.0098) 0.10 (0.0040) COPLANARITY 0.51 (0.0201) 0.10 0.31 (0.0122) ...
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... AD8571ARZ 1 −40°C to +125°C 1 AD8571ARZ-REEL −40°C to +125°C AD8571ARZ-REEL7 1 −40°C to +125°C AD8571ARM-R2 −40°C to +125°C AD8571ARM-REEL −40°C to +125°C 1 AD8571ARMZ-R2 −40°C to +125°C 1 AD8571ARMZ-REEL −40°C to +125°C AD8572AR −40°C to +125°C AD8572AR-REEL − ...
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... AD8571/AD8572/AD8574 NOTES ©1999-2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01104-0-5/07(C) Rev Page ...