AD8208

AD8208 (Rev. C)

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High Voltage, Precision Difference Amplifier Data Sheet AD8208 Rev. C Document Feedback 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. Tel: 781.329.4700 © 2010–2013 Analog Devices, Inc. All rights reserved. Technical Support www.analog.com

FEATURES

Qualified for automotive applications EMI filters included High common-mode voltage range −2 V to +45 V operating −24 V to +80 V survival Buffered output voltage Gain = 20 V/V Low-pass filter (1-pole or 2-pole) Wide operating temperature range −40°C to +125°C for WB grade −40°C to +150°C for WH grade Excellent ac and dc performance ±1 mV voltage offset −5 ppm/°C typical gain drift 80 dB CMRR minimum dc to 10 kHz

APPLICATIONS

+IN –IN GND VS AD8208 G = 2G = 10 A1 A2 EMI FILTER EMI FILTER EMI FILTER Figure 1. GENERAL DESCRIPTION The AD8208 is a single-supply difference amplifier ideal for amplifying and low-pass filtering small differential voltages in the presence of a large common-mode voltage. The input common- mode voltage range extends from −2 V to +45 V at a single +5 V supply. The AD8208 is qualified for automotive applications. The amplifier offers enhanced input overvoltage and ESD protection, and includes EMI filtering. Automotive applications demand robust, precision components for improved system control. The AD8208 provides excellent ac and dc performance, minimizing errors in the application. Typical offset and gain drift in both the SOIC and MSOP packages are less than 5 µV/°C and 10 ppm/°C, respectively. The device also delivers a minimum CMRR of 80 dB from dc to 10 kHz. The AD8208 features an externally accessible 100 kΩ resistor at the output of the preamplifier (A1), which can be used for low- pass filtering and for establishing gains other than 20.

Rev. C | Page 2 of 20 TABLE OF CONTENTS High Line Current Sensing with LPF and Gain Adjustment 15

REVISION HISTORY

12/13---- - Rev. B to Rev. C Ch 2/13—Rev. A to Rev. B 5/10—Rev. 0 to Rev. A Changes to Features Section a nd General Description Section .. 1 1/10—Revision 0: Initial Version

Rev. C | Page 3 of 20 SPECIFICATIONS TOPR = −40°C to +125°C for AD8208WBR and AD8208WBRM grade, TOPR = −40°C to +150°C for AD8208WHR grade, TA = 25°C, VS = 5 V, RL = 25 kΩ (RL is the output load resistor), unless otherwise noted. Specifications applicable for both packages (SOIC and MSOP). Table 1. Parameter Test Conditions1 Min Typ Max Unit SYSTEM GAIN Initial 20 V/V Error vs. Temperature 0.075 V ≤ VOUT ≤ (VS − 0.1 V), dc, TOPR ±0.3 % Gain Drift TOPR 0 −20 ppm/°C VOLTAGE OFFSET Initial Input Offset (Referred to Input [RTI]) VCM = 0.15 V, TA ±2 mV Input Offset (RTI) Over Temperature VCM = 0 V, TOPR ±4 mV Voltage Offset vs. Temperature VCM = 0 V, TOPR −20 +20 µV/°C INPUT Input Impedance Differential 360 400 440 kΩ Common Mode 180 200 220 kΩ VCM (Continuous) −2 +45 V CMRR2 VCM = −2 V to +45 V, dc 80 100 dB f = dc to 10 kHz,3 TOPR 80 dB PREAMPLIFIER (A1) Gain 10 V/V Gain Error 0.05 V ≤ VOUT ≤ (VS − 0.1 V), dc, TOPR −0.3 +0.3 % Output Voltage Range AD8208WBR, AD8208WBRM 0.0375 VS − 0.1 V AD8208WHR, AD8208WHRM 0.05 VS − 0.1 V Output Resistance 97 100 103 kΩ OUTPUT BUFFER (A2) Gain 2 V/V Gain Error 0.075 V ≤ VOUT ≤ (VS − 0.1 V), dc, TOPR −0.3 +0.3 % Output Voltage Range4, 5 RL = 25 kΩ, differential Input (V) = 0 V, TOPR Pin 3 (A1 output) driving Pin 4 (A2 input) AD8208WBR, AD8208WBRM 0.075 VS − 0.1 V AD8208WHR, AD8208WHRM 0.1 VS − 0.12 V Output Voltage Range6 Pin 4 (A2 input) driven with external source AD8208WBR, AD8208WBRM 0.075 VS − 0.1 V AD8208WHR, AD8208WHRM 0.1 VS − 0.12 V Input Bias Current TOPR 50 nA Output Resistance RL = 1 kΩ, frequency = dc 2 Ω DYNAMIC RESPONSE System Bandwidth VIN = 0.01 V p-p, VOUT = 0.14 V p-p 70 kHz Slew Rate VIN = 0.28 V, VOUT = 4 V step 1 V/µs NOISE

0.1 Hz to 10 Hz 20 µV p-p

Spectral Density, 1 kHz (RTI) 500 nV/√Hz POWER SUPPLY Operating Range 4.5 5.5 V Quiescent Current Typical, TA 1.6 mA Quiescent Current vs. Temperature VOUT = 0.1 V dc, VS = 5 V, TOPR AD8208WBR, AD8208WBRM 2.7 mA AD8208WHR, AD8208WHRM 3.0 mA PSRR VS = 4.5 V to 5.5 V, TOPR 66 80 dB

Rev. C | Page 4 of 20 Parameter Test Conditions1 Min Typ Max Unit TEMPERATURE RANGE For Specified Performance at TOPR AD8208WBR, AD8208WBRM −40 +125 °C AD8208WHR, AD8208WHRM −40 +150 °C 1 VCM = input common-mode voltage. 2 Source imbalance < 2 Ω. 3 The AD8208 pr eamplifier exceeds 80 dB CMRR at 10 kHz. However, because the output is available only by way of the 100 kΩ resistor, even a small amount of pin-to- pin capacitance between the IN pins and the A1 and A2 pins might couple an input common-mode signal larger than the greatly attenuated preamplifier output. The effect of pin-to-pin coupling can be negated in all applications by using a filter capacitor from Pin 3 to GND. 4 The output voltage range of the AD8208 varies depending on the load resistance and temperature. For additional information on this specification, see Figure 12 and Figure 13. 5 The output voltage range of A2 assumes that Pin 3 (A1 output) and Pin 4 (A2 Input) are shorted together. A 25 kΩ load resistor used for testing. 6 The output voltage range of A2 assumes Pin 4 (A2 Input) is driven with an external voltage source. A 25 kΩ load resistor was used for testing.

Rev. C | Page 5 of 20 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Rating Supply Voltage 12 V Continuous Input Voltage (Common Mode) −24 V to +80 V Differential Input Voltage ±12 V Reversed Supply Voltage Protection 0.3 V ESD Human Body Model ±4000 V Operating Temperature Range WBR and WBRM Grade −40°C to +125°C WHR and WHRM Grade −40°C to +150°C Storage Temperature Range −65°C to +150°C Output Short-Circuit Duration Indefinite Lead Temperature Range (Soldering, 10 sec) 300°C Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ESD CAUTION

Figure 2. Pin Configuration Figure 3. Metallization Photograph Table 3. Pin Function Descriptions

2 GND −321 +208 Ground

3 A1 −321 −51 Preamplifier (A1) Output

4 A2 −321 −214 Buffer (A2) Input

5 OUT +321 −388 Buffer (A2) Output

6 VS +322 +363 Supply

7 NC No Connect

REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 38. 8-Lead Standard Small Outline Package [SOIC_N]

0.65 BSC

1.10 MAX

Figure 39. 8-Lead Mini Small Outline Package [MSOP]

Rev. C | Page 17 of 20 ORDERING GUIDE Model1, 2 Temperature Range Package Description Package Option Branding AD8208WBRZ −40°C to +125°C 8-Lead SOIC_N R-8 AD8208WBRZ-R7 −40°C to +125°C 8-Lead SOIC_N, 7” Tape and Reel R-8 AD8208WBRZ-RL −40°C to +125°C 8-Lead SOIC_N, 13” Tape and Reel R-8 AD8208WBRMZ −40°C to +125°C 8-Lead Mini Small Outline Package [MSOP] RM-8 Y2F AD8208WBRMZ-R7 −40°C to +125°C 8-Lead Mini Small Outline Package [MSOP], 7” Tape and Reel RM-8 Y2F AD8208WBRMZ-RL −40°C to +125°C 8-Lead Mini Small Outline Package [MSOP], 13” Tape and Reel RM-8 Y2F AD8208WHRZ −40°C to +150°C 8-Lead SOIC_N R-8 AD8208WHRZ-RL −40°C to +150°C 8-Lead SOIC_N, 13” Tape and Reel R-8 AD8208WHRMZ −40°C to +150°C 8-Lead Mini Small Outline Package [MSOP] RM-8 Y52 AD8208WHRMZ-RL −40°C to +150°C 8-Lead Mini Small Outline Package [MSOP], 13” Tape and Reel RM-8 Y52 1 Z = RoHS Compliant Part. 2 W = Qualified for Automotive Applications. AUTOMOTIVE PRODUCTS The AD8208W models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these models.

Rev. C | Page 18 of 20 NOTES

Rev. C | Page 19 of 20 NOTES

Rev. C | Page 20 of 20 NOTES ©2010–2013 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08714-0-12/ 13(C)