AD524

Precision Instrumentation Amplifier AD524 FEATURES Low noise: 0.3 μV p-p at 0.1 Hz to 10 Hz Low nonlinearity: 0.003% (G = 1) High CMRR: 120 dB (G = 1000) Low offset voltage: 50 μV Low offset voltage drift: 0.5 μV/°C Gain bandwidth product: 25 MHz Pin programmable gains of 1, 10, 100, 1000 Input protection, power-on/power-off No external components required Internally compensated MIL-STD-883B and chips available 16-lead ceramic DIP and SOIC packages and 20-terminal leadless chip carrier available Available in tape and reel in accordance with EIA-481A standard Standard military drawing also available – INPUT 1 G = 10 13 G = 100 12 G = 1000 11 RG1 16 RG2 3 FUNCTIONAL BLOCK DIAGRAM PROTECTION 4.44kΩ 404Ω 40Ω Vb 20kΩ 20kΩ OUTPUT 20kΩ 20kΩ 20kΩ 20kΩ SENSE AD524 REFERENCE 00500-001 + INPUT 2 PROTECTION Figure 1. GENERAL DESCRIPTION The AD524 is a precision monolithic instrumentation amplifier designed for data acquisition applications requiring high accuracy under worst-case operating conditions. An outstanding combination of high linearity, high common-mode rejection, low offset voltage drift, and low noise makes the AD524 suitable for use in many data acquisition systems. The AD524 has an output offset voltage drift of less than 25 μV/°C, input offset voltage drift of less than 0.5 μV/°C, CMR above 90 dB at unity gain (120 dB at G = 1000), and maximum nonlinearity of 0.003% at G = 1. In addition to the outstanding dc specifications, the AD524 also has a 25 kHz bandwidth (G = 1000). To make it suitable for high speed data acquisition systems, the AD524 has an output slew rate of 5 V/μs and settles in 15 μs to 0.01% for gains of 1 to 100. As a complete amplifier, the AD524 does not require any external components for fixed gains of 1, 10, 100 and 1000. For other gain settings between 1 and 1000, only a single resistor is required. The AD524 input is fully protected for both power-on and power-off fault conditions. The AD524 IC instrumentation amplifier is available in four different versions of accuracy and operating temperature range. The economical A grade, the low drift B grade, and lower drift, higher linearity C grade are specified from −25°C to +85°C. The S grade guarantees performance to specification over the extended temperature range −55°C to +125°C. The AD524 is available in a 16-lead ceramic DIP, 16-lead SBDIP, 16-lead SOIC wide packages, and 20-terminal leadless chip carrier. PRODUCT HIGHLIGHTS 1. The AD524 has guaranteed low offset voltage, offset voltage drift, and low noise for precision high gain applications. The AD524 is functionally complete with pin programmable gains of 1, 10, 100, and 1000, and single resistor programmable for any gain. Input and output offset nulling terminals are provided for very high precision applications and to minimize offset voltage changes in gain ranging applications. The AD524 is input protected for both power-on and power-off fault conditions. The AD524 offers superior dynamic performance with a gain bandwidth product of 25 MHz, full power response of 75 kHz and a settling time of 15 μs to 0.01% of a 20 V step (G = 100). 2. 3. 4. 5. Rev. F Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved. AD524 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 8 Connection Diagrams .................................................................. 8 ESD Caution .................................................................................. 8 Typical Performance Characteristics ............................................. 9 Test Circuits ................................................................................. 14 Theory of Operation ...................................................................... 15 Input Protection.......................................................................... 15 Input Offset and Output Offset ................................................ 15 Gain .............................................................................................. 16 Input Bias Currents .................................................................... 17 Common-Mode Rejection ........................................................ 17 Grounding ................................................................................... 18 Sense Terminal............................................................................ 18 Reference Terminal .................................................................... 18 Programmable Gain ................................................................... 20 Autozero Circuits ....................................................................... 20 Error Budget Analysis ................................................................ 21 Outline Dimensions ....................................................................... 24 Ordering Guide .......................................................................... 25 REVISION HISTORY 11/07—Rev. E to Rev. F Updated Format .................................................................. Universal Changes to General Description .................................................... 1 Changes to Figure 1 .......................................................................... 1 Changes to Figure 3 and Figure 4 Captions .................................. 8 Changes to Error Budget Analysis Section ................................. 21 Changes to Ordering Guide .......................................................... 25 4/99—Rev. D to Rev. E Rev. F | Page 2 of 28 AD524 SPECIFICATIONS @ VS = ±15 V, RL = 2 kΩ and TA = +25°C, unless otherwise noted. All min and max specifications are guaranteed. Specifications shown in boldface are tested on all production units at the final electrical test. Results from those tests are used to calculate outgoing quality levels. Table 1. Parameter GAIN Gain Equation (External Resistor Gain Programming) Min AD524A Typ Max Min AD524B Typ Max Unit ⎡ 40 ,000 ⎤ + 1⎥ ± 20% ⎢ ⎣ RG ⎦ 1 to 1000 ±0.05 ±0.25 ±0.5 ±2.0 ±0.01 ±0.01 ±0.01 5 15 35 100 250 2 5 100 70 85 95 100 ±50 ±100 ±35 ±100 ⎡ 40 ,000 ⎤ + 1⎥ ± 20% ⎢ ⎣ RG ⎦ 1 to 1000 ±0.03 ±0.15 ±0.35 ±1.0 ±0.005 ±0.005 ±0.01 5 10 25 50 100 0.75 3 50 75 95 105 110 ±25 ±100 ±15 ±100 % % % % % % % ppm/°C ppm/°C ppm/°C ppm/°C μV μV/°C mV μV dB dB dB dB nA pA/°C nA pA/°C Gain Range (Pin Programmable) Gain Error 1 G=1 G = 10 G = 100 G = 1000 Nonlinearity G=1 G = 10, G = 100 G = 1000 Gain vs. Temperature G=1 G = 10 G = 100 G = 1000 VOLTAGE OFFSET (May be Nulled) Input Offset Voltage vs. Temperature Output Offset Voltage vs. Temperature Offset Referred to the Input vs. Supply G=1 G = 10 G = 100 G = 1000 INPUT CURRENT Input Bias Current vs. Temperature Input Offset Current vs. Temperature Rev. F | Page 3 of 28 AD524 Parameter INPUT Input Impedance Differential Resistance Differential Capacitance Common-Mode Resistance Common-Mode Capacitance Input Voltage Range Maximum Differential Input Linear (VDL) 2 Maximum Common-Mode Linear (VCM)2 Common-Mode Rejection DC to 60 Hz with 1 kΩ Source Imbalance G=1 G = 10 G = 100 G = 1000 OUTPUT RATING VOUT, RL = 2 kΩ DYNAMIC RESPONSE Small Signal – 3 dB G=1 G = 10 G = 100 G = 1000 Slew Rate Settling Time to 0.01%, 20 V Step G = 1 to 100 G = 1000 NOISE Voltage Noise, 1 kHz RTI RTO RTI, 0.1 Hz to 10 Hz G=1 G = 10 G = 100, 1000 Current Noise 0.1 Hz to 10 Hz SENSE INPUT RIN IIN Voltage Range Gain to Output REFERENCE INPUT RIN IIN Voltage Range Gain to Output Min AD524A Typ Max Min AD524B Typ Max Unit 109 10 109 10 ±10 ±10 109 10 109 10 Ω pF Ω pF V V V dB dB dB dB ⎛G ⎞ 12 V − ⎜ × VD ⎟ 2 ⎝ ⎠ 70 90 100 110 ±10 75 95 105 115 ⎛G ⎞ 12 V − ⎜ × VD ⎟ 2 ⎝ ⎠ ±10 V 1 400 150 25 5.0 15 75 1 400 150 25 5.0 15 75 MHz kHz kHz kHz V/μs μs μs 7 90 15 2 0.3 60 20 15 ±10 1 40 15 ±10 1 ±10 ±10 7 90 15 2 0.3 60 20 15 1 40 15 1 nV/√Hz nV√Hz μV p-p μV p-p μV p-p pA p-p kΩ ± 20% μA V % kΩ ± 20% μA V % Rev. F | Page 4 of 28 AD524 Parameter TEMPERATURE RANGE Specified Performance Storage POWER SUPPLY Power Supply Range Quiescent Current 1 2 Min –25 –65 ±6 AD524A Typ Max +85 +150 ±15 3.5 ±18 5.0 Min –25 –65 ±6 AD524B Typ Max +85 +150 ±15 3.5 ±18 5.0 Unit °C °C V mA Does not include effects of external resistor, RG. VOL is the maximum differential input voltage at G = 1 for specified nonlinearity. VDL at the maximum = 10 V/G. VD = actual differential input voltage. Example: G = 10, VD = 0.50. VCM = 12 V − (10/2 × 0.50 V) = 9.5 V. @ VS = ±15 V, RL = 2 kΩ and TA = +25°C, unless otherwise noted. All min and max specifications are guaranteed. Specifications shown in boldface are tested on all production units at the final electrical test. Results from those tests are used to calculate outgoing quality levels. Table 2. Parameter GAIN Gain Equation (External Resistor Gain Programming) Min AD524C Typ Max Min AD524S Typ Max Unit ⎡ 40 ,000 ⎤ + 1⎥ ± 20% ⎢ ⎣ RG ⎦ 1 to 1000 ±0.02 ±0.1 ±0.25 ±0.5 ±0.003 ±0.003 ±0.01 5 10 25 50 50 0.5 2.0 25 80 100 110 115 ⎡ 40 ,000 ⎤ + 1⎥ ± 20% ⎢ ⎣ RG ⎦ 1 to 1000 ±0.05 ±0.25 ±0.5 ±2.0 ±0.01 ±0.01 ±0.01 5 10 25 50 100 2.0 3.0 50 75 95 105 110 % % % % % % % ppm/°C ppm/°C ppm/°C ppm/°C μV μV/°C mV μV dB dB dB dB Gain Range (Pin Programmable) Gain Error 1 G=1 G = 10 G = 100 G = 1000 Nonlinearity G=1 G = 10, G = 100 G = 1000 Gain vs. Temperature G=1 G = 10 G = 100 G = 1000 VOLTAGE OFFSET (May be Nulled) Input Offset Voltage vs. Temperature Output Offset Voltage vs. Temperature Offset Referred to the Input vs. Supply G=1 G = 10 G = 100 G = 1000 Rev. F | Page 5 of 28 AD524 Parameter INPUT CURRENT Input Bias Current vs. Temperature Input Offset Current vs. Temperature INPUT Input Impedance Differential Resistance Differential Capacitance Common-Mode Resistance Common-Mode Capacitance Input Voltage Range Maximum Differential Input Linear (VDL) 2 Maximum Common-Mode Linear (VCM)2 Common-Mode Rejection DC to 60 Hz with 1 kΩ Source Imbalance G=1 G = 10 G = 100 G = 1000 OUTPUT RATING VOUT, RL = 2 kΩ DYNAMIC RESPONSE Small Signal – 3 dB G=1 G = 10 G = 100 G = 1000 Slew Rate Settling Time to 0.01%, 20 V Step G = 1 to 100 G = 1000 NOISE Voltage Noise, 1 kHz RTI RTO RTI, 0.1 Hz to 10 Hz G=1 G = 10 G = 100, 1000 Current Noise 0.1 Hz to 10 Hz SENSE INPUT RIN IIN Voltage Range Gain to Output Min AD524C Typ Max ±15 ±100 ±10 ±100 ±100 ±100 ±35 Min AD524S Typ Max ±50 Unit nA pA/°C nA pA/°C 109 10 109 10 ±10 ±10 109 10 109 10 Ω pF Ω pF V V V dB dB dB dB ⎛G ⎞ 12 V − ⎜ × VD ⎟ ⎝2 ⎠ 80 100 110 120 ±10 70 90 100 110 ⎛G ⎞ 12 V − ⎜ × VD ⎟ ⎝2 ⎠ ±10 V 1 400 150 25 5.0 15 75 1 400 150 25 5.0 15 75 MHz kHz kHz kHz V/μs μs μs 7 90 15 2 0.3 60 20 15 ±10 1 ±10 7 90 15 2 0.3 60 20 15 1 nV/√Hz nV√Hz μV p-p μV p-p μV p-p pA p-p kΩ ± 20% μA V % Rev. F | Page 6 of 28 AD524 Parameter REFERENCE INPUT RIN IIN Voltage Range Gain to Output TEMPERATURE RANGE Specified Performance Storage POWER SUPPLY Power Supply Range Quiescent Current 1 2 Min AD524C Typ Max 40 15 Min AD524S Typ Max 40 15 Unit kΩ ± 20% μA V % 10 1 –25 –65 ±6 ±15 3.5 +85 +150 ±18 5.0 10 1 –55 –65 ±6 ±15 3.5 +85 +150 ±18 5.0 °C °C V mA Does not include effects of external resistor RG. VOL is the maximum differential input voltage at G = 1 for specified nonlinearity. VDL at the maximum = 10 V/G. VD = actual differential input voltage. Example: G = 10, VD = 0.50. VCM = 12 V − (10/2 × 0.50 V) = 9.5 V. Rev. F | Page 7 of 28 AD524 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Supply Voltage Internal Power Dissipation Input Voltage1 (Either Input Simultaneously) |VIN| + |VS| Output Short-Circuit Duration Storage Temperature Range (R) (D, E) Operating Temperature Range AD524A/AD524B/AD524C AD524S Lead Temperature (Soldering, 60 sec) 1 CONNECTION DIAGRAMS Rating ±18 V 450 mW