AD8222 Analog Devices, AD8222 Datasheet
AD8222
Available stocks
Related parts for AD8222
AD8222 Summary of contents
Page 1
... AD526 AD624 1 Rail-to-rail output. The AD8222 maintains a minimum CMRR kHz for all grades High CMRR over frequency allows the AD8222 to reject wideband interference and line harmonics, greatly simplifying filter requirements. The AD8222 also has a typical CMRR drift over temperature of just 0.07 μV/V/° ...
Page 2
... AD8222 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 6 Thermal Resistance ...................................................................... 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 15 Amplifier Architecture .............................................................. 15 Gain Selection ............................................................................. 15 Reference Terminal .................................................................... 16 REVISION HISTORY 7/06—Revision 0: Initial Version Layout ...
Page 3
... ± 0.0001 AD8222 Max Unit μV/V/°C 8 nV/√Hz 75 nV/√Hz μV p-p μV p-p μV p-p fA/√Hz pA p-p 60 μV 80 μV 0.3 μV/°C 350 μV 0.5 ...
Page 4
... AD8222 Parameter Conditions GAIN (49.4 kΩ/R Gain Range Gain Error V OUT 100 G = 1000 Gain Nonlinearity V OUT 100 Gain vs. Temperature > 1 INPUT Input Impedance Differential Common Mode 3 Input Operating Voltage Range V S Overtemperature T = −40°C to +85°C ...
Page 5
... Performance A Grade Conditions Min Typ 1000 650 140 step step 18 110 1 1000 2 2.5 Rev Page AD8222 B Grade Max Min Typ Max 1200 750 140 110 1 2.5 B Grade Max Min Typ Max 1000 ...
Page 6
... Maximum Power Dissipation The maximum safe power dissipation for the AD8222 is limited by the associated rise in junction temperature (T approximately 130°C, which is the glass transition temperature, the plastic changes its properties. Even temporarily exceeding ...
Page 7
... Gain Resistor In-Amp 1 Gain Resistor In-Amp 1 Positive Input In-Amp 1 Positive Supply Reference Adjust In-Amp 1 Reference Adjust In-Amp 2 Negative Supply Positive Input In-Amp 2 Gain Resistor In-Amp 2 Gain Resistor In-Amp 2 Negative Input In-Amp 2 Negative Supply Output In-Amp 2 Output In-Amp 1 Positive Supply Rev Page AD8222 ...
Page 8
... AD8222 TYPICAL PERFORMANCE CHARACTERISTICS 500 400 300 200 100 0 –50 –40 –30 –20 – CMRR (µV/V) Figure 3. Typical Distribution for CMRR ( 300 250 200 150 100 10 0 –100 (µV) OSI Figure 4. Typical Distribution of Input Offset Voltage ...
Page 9
... Figure 13. Negative PSRR vs. Frequency, RTI ( 1000) 10k 1k 100 GAIN = 105 125 1 Rev Page AD8222 BANDWIDTH LIMITED GAIN = 1000 GAIN = 100 GAIN = 10 GAIN = 100 1k 10k 100k FREQUENCY (Hz) GAIN = 1000 GAIN = 100 GAIN = 10 GAIN = ...
Page 10
... AD8222 70 GAIN = 1000 60 50 GAIN = 100 40 30 GAIN = GAIN = 1 0 –10 –20 –30 –40 100 1k 10k 100k FREQUENCY (Hz) Figure 15. Gain vs. Frequency 160 GAIN = 1000 150 GAIN = 100 140 130 GAIN = 10 120 110 GAIN = 1 100 0 100 1k FREQUENCY (Hz) Figure 16 ...
Page 11
... LOAD 10kΩ LOAD –8 –6 –4 – (V) OUT Figure 24. Gain Nonlinearity 100 GAIN = 1 GAIN = 10 GAIN = 100 GAIN = 1000 GAIN = 1000 BW LIMIT 10 100 1k 10k FREQUENCY (Hz) 1s/DIV Figure 26. 0 RTI Voltage Noise ( AD8222 8 10 100k ...
Page 12
... AD8222 0.1µV/DIV Figure 27. 0 RTI Voltage Noise (G = 1000) 1k 100 100 1k FREQUENCY (Hz) Figure 28. Current Noise Spectral Density vs. Frequency 5pA/DIV Figure 29. 0 Current Noise 1s/DIV 1k 10k 100k Figure 31. Large Signal Pulse Response and Settling Time ( 1s/DIV Figure 32 ...
Page 13
... Figure 36. Small Signal Response 10, R 20mV/DIV 200µs/DIV Figure 37. Small Signal Response 100, R 4µs/DIV 20mV/DIV = 100 pF Figure 38. Small Signal Response 1000 Rev Page AD8222 4µs/DIV = 2 kΩ 100 10µs/DIV = 2 kΩ 100 100µ ...
Page 14
... AD8222 15 10 SETTLED TO 0.001% SETTLED TO 0.01 OUTPUT VOLTAGE STEP SIZE (V) Figure 39. Settling Time vs. Step Size ( 100 SETTLED TO 0.001% 10 SETTLED TO 0.01 GAIN Figure 40. Settling Time vs. Gain for Step 200 SOURCE V = 20V p-p OUT 180 GAIN = 1000 160 THERMAL CROSSTALK ...
Page 15
... The AD8222 defaults when no gain resistor is used. The tolerance and gain drift of the R to the AD8222’s specifications to determine the total gain accuracy of the system. When the gain resistor is not used, gain error and gain drift are kept to a minimum. ...
Page 16
... The AD8222 pinout is arranged in a logical manner to aid in this task. Package Considerations The AD8222 comes × LFCSP. Beware of blindly copying the footprint from another 4 mm × LFCSP part; it may not have the same thermal pad size and leads ...
Page 17
... AD8222’s excellent bias current performance. INPUT BIAS CURRENT RETURN PATH The input bias current of the AD8222 must have a return path to common. When the source, such as a thermocouple, cannot provide a return current path, one should be created, as shown in Figure 47 ...
Page 18
... D the mismatch is reduced and performance is improved. COMMON-MODE INPUT VOLTAGE RANGE The three op amp architecture of the AD8222 applies gain and then removes the common-mode voltage. Therefore, internal nodes in the AD8222 experience a combination of both the gained signal and the common-mode signal. This combined signal can be limited by the voltage supplies even when the individual input and output signals are not ...
Page 19
... APPLICATIONS DIFFERENTIAL OUTPUT The differential configuration of the AD8222 has the same excellent dc precision specifications as the single-ended output configuration and is recommended for applications in the frequency range 100 kHz. The circuit configuration is shown in Figure 49. The differential output specification in Table 2 and Table 4 refer to this configuration only ...
Page 20
... ADC. PRECISION STRAIN GAUGE The low offset and high CMRR over frequency of the AD8222 make it an excellent candidate for both ac and dc bridge measurements. As shown in Figure 52, the bridge can be connected to the inputs of the amplifier directly. ...
Page 21
... The capacitive load from the cable may cause peaking in the AD8222’s output response. To reduce the peaking, use a resistor between the AD8222 and the cable. Because cable capacitance and desired output response vary widely, this resistor is best determined empirically. A good starting point is 50 Ω ...
Page 22
... Model Temperature Range 1 AD8222ACPZ-R7 −40°C to +85°C 1 AD8222ACPZ-RL −40°C to +85°C 1 AD8222ACPZ-WP −40°C to +85°C AD8222BCPZ-R7 1 −40°C to +85°C 1 AD8222BCPZ-RL −40°C to +85°C 1 AD8222BCPZ-WP −40°C to +85°C AD8222-EVAL Pb-free part. 4.00 0.60 MAX BSC 3.75 EXPOSED BSC SQ 0 ...
Page 23
... NOTES Rev Page AD8222 ...
Page 24
... AD8222 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05947-0-7/06(0) Rev Page ...