AD8274

Very Low Distortion, Precision Difference Amplifier AD8274 FEATURES Very low distortion 0.00025% THD + N (20 kHz) 0.0015% THD + N (100 kHz) Drives 600 Ω loads Excellent gain accuracy 0.03% maximum gain error 2 ppm/°C maximum gain drift Gain of ½ or 2 AC specifications 20 V/μs minimum slew rate 800 ns to 0.01% settling time High accuracy dc performance 83 dB minimum CMRR 700 μV maximum offset voltage 8-lead SOIC and MSOP packages Supply current: 2.6 mA maximum Supply range: ±2.5 V to ±18 V FUNCTIONAL BLOCK DIAGRAM +VS 7 2 12kΩ 6kΩ 5 6 3 12kΩ 6kΩ 1 –VS Figure 1. Table 1. Difference Amplifiers by Category Low Distortion AD8270 AD8273 AD8274 AMP03 High Voltage AD628 AD629 Single-Supply Unidirectional AD8202 AD8203 Single-Supply Bidirectional AD8205 AD8206 AD8216 APPLICATIONS ADC driver High performance audio Instrumentation amplifier building blocks Level translators Automatic test equipment Sine/cosine encoders GENERAL DESCRIPTION The AD8274 is a difference amplifier that delivers excellent ac and dc performance. Built on Analog Devices, Inc., proprietary iPolar® process and laser-trimmed resistors, AD8274 achieves a breakthrough in distortion vs. current consumption and has excellent gain drift, gain accuracy, and CMRR. Distortion in the audio band is an extremely low 0.00025% (112 dB) at a gain of ½ and 0.00035% (109 dB) at a gain of 2 while driving a 600 Ω load With supply voltages up to ±18 V (+36 V single supply), the AD8274 is well suited for measuring large industrial signals. Additionally, the part’s resistor divider architecture allows it to measure voltages beyond the supplies. With no external components, the AD8274 can be configured as a G = ½ or G = 2 difference amplifier. For single-ended applications that need high gain stability or low distortion performance, the AD8274 can also be configured for several gains ranging from −2 to +3. The excellent distortion and dc performance of the AD8274, along with its high slew rate and bandwidth, make it an excellent ADC driver. Because of the part’s high output drive, it also makes a very good cable driver. The AD8274 only requires 2.6 mA maximum supply current. It is specified over the industrial temperature range of −40°C to +85°C and is fully RoHS compliant. For the dual version, see the AD8273 data sheet. Rev. A 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 ©2008 Analog Devices, Inc. All rights reserved. 07362-001 4 AD8274 TABLE OF CONTENTS Features .............................................................................................. 1  Applications ....................................................................................... 1  Functional Block Diagram .............................................................. 1  General Description ......................................................................... 1  Revision History ............................................................................... 2  Specifications..................................................................................... 3  Absolute Maximum Ratings............................................................ 4  Thermal Resistance ...................................................................... 4  Maximum Power Dissipation ..................................................... 4  Short-Circuit Current .................................................................. 4  ESD Caution .................................................................................. 4  Pin Configurations and Function Description..............................5  Typical Performance Characteristics ..............................................6  Theory of Operation ...................................................................... 12  Circuit Information.................................................................... 12  Driving the AD8274................................................................... 12  Power Supplies ............................................................................ 12  Input Voltage Range ................................................................... 12  Configurations ............................................................................ 13  Driving Cabling .......................................................................... 14  Outline Dimensions ....................................................................... 15  Ordering Guide .......................................................................... 15  REVISION HISTORY 12/08—Rev. 0 to Rev. A Changes to Figure 8 and Figure 10 ................................................. 6 7/08—Revision 0: Initial Version Rev. A | Page 2 of 2 AD8274 SPECIFICATIONS VS = ±15 V, VREF = 0 V, TA = 25°C, RL = 2 kΩ, unless otherwise noted. Table 2. Parameter DYNAMIC PERFORMANCE Bandwidth Slew Rate Settling Time to 0.1% Settling Time to 0.01% NOISE/DISTORTION 1 THD + Noise Noise Floor, RTO 2 Output Voltage Noise (Referred to Output) GAIN Gain Error Gain Drift Gain Nonlinearity INPUT CHARACTERISTICS Offset 3 vs. Temperature vs. Power Supply Common-Mode Rejection Ratio Input Voltage Range 4 Impedance 5 Differential Common Mode 6 OUTPUT CHARACTERISTICS Output Swing Short-Circuit Current Limit Capacitive Load Drive POWER SUPPLY Supply Current (per Amplifier) TEMPERATURE RANGE Specified Performance 1 2 3 Conditions Min G=½ Typ 20 Max Min G=2 Typ 10 Max Unit MHz V/μs ns ns % dBu μV rms nV/√Hz 20 10 V step on output, CL = 100 pF 10 V step on output, CL = 100 pF f = 1 kHz, VOUT = 10 V p-p, 600 Ω load 20 kHz BW f = 20 Hz to 20 kHz f = 1 kHz 650 725 0.00025 −106 3.5 26 0.03 2 750 800 20 675 750 0.00035 −100 7 52 0.03 2 775 825 −40°C to +85°C VOUT = 10 V p-p, 600 Ω load Referred to output −40°C to +85°C VS = ±2.5 V to ±18 V VCM = ±40 V, RS = 0 Ω, referred to input 0.5 2 150 3 77 −3VS + 4.5 86 0.5 2 300 6 83 92 % ppm/°C ppm μV μV/°C μV/V dB V 700 5 1100 10 +3VS − 4.5 24 9 −1.5VS + 2.3 12 9 +1.5VS − 2.3 VCM = 0 V kΩ kΩ +VS − 1.5 V mA mA pF 2.6 +85 mA °C −VS + 1.5 Sourcing Sinking 90 60 200 2.3 −40 +VS − 1.5 −VS + 1.5 90 60 1200 2.6 +85 −40 2.3 Includes amplifier voltage and current noise, as well as noise of internal resistors. dBu = 20 log(V rms/0.7746). Includes input bias and offset current errors. 4 May also be limited by absolute maximum input voltage or by the output swing. See the Absolute Maximum Ratings section and Figure 8 through Figure 11 for details. 5 Internal resistors are trimmed to be ratio matched but to have ±20% absolute accuracy. 6 Common mode is calculated by looking into both inputs. The common-mode impedance at only one input is 18 kΩ. Rev. A | Page 3 of 3 AD8274 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Supply Voltage Maximum Voltage at Any Input Pin Minimum Voltage at Any Input Pin Storage Temperature Range Specified Temperature Range Package Glass Transition Temperature (TG) Rating ±18 V −VS + 40 V +VS – 40 V −65°C to +150°C −40°C to +85°C 150°C MAXIMUM POWER DISSIPATION The maximum safe power dissipation for the AD8274 is limited by the associated rise in junction temperature (TJ) on the die. At approximately 150°C, which is the glass transition temperature, the properties of the plastic change. Even temporarily exceeding this temperature limit may change the stresses that the package exerts on the die, permanently shifting the parametric performance of the amplifiers. Exceeding a temperature of 150°C for an extended period may result in a loss of functionality. 2.0 TJ MAX = 150°C MAXIMUM POWER DISSIPATION (W) 1.6 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. 1.2 SOIC θJA = 121°C/W MSOP θJA = 135°C/W THERMAL RESISTANCE The θJA values in Table 4 assume a 4-layer JEDEC standard board with zero airflow. Table 4. Thermal Resistance Package Type 8-Lead MSOP 8-Lead SOIC θJA 135 121 Unit °C/W °C/W 0.8 0.4 07362-004 0 –50 –25 0 25 50 75 100 125 AMBIENT TEMERATURE (°C) Figure 2. Maximum Power Dissipation vs. Ambient Temperature SHORT-CIRCUIT CURRENT The AD8274 has built-in, short-circuit protection that limits the output current (see Figure 16 for more information). While the short-circuit condition itself does not damage the part, the heat generated by the condition can cause the part to exceed its maximum junction temperature, with corresponding negative effects on reliability. Figure 2 and Figure 16, combined with knowledge of the part’s supply voltages and ambient temperature, can be used to determine whether a short circuit will cause the part to exceed its maximum junction temperature. ESD CAUTION Rev. A | Page 4 of 4 AD8274 PIN CONFIGURATIONS AND FUNCTION DESCRIPTION REF 1 –IN 2 +IN 3 –VS 4 8 AD8274 TOP VIEW (Not to Scale) NC +VS OUT 07362-002 REF 1 –IN 2 +IN 3 8 NC +VS SENSE 07362-003 7 6 5 AD8274 7 6 5 SENSE TOP VIEW –VS 4 (Not to Scale) OUT NC = NO CONNECT NC = NO CONNECT Figure 3. MSOP Pin Configuration Figure 4. SOIC Pin Configuration Table 5. Pin Function Descriptions Pin No. 1 2 3 4 5 6 7 8 Mnemonic REF −IN +IN −VS SENSE OUT +VS NC Description 6 kΩ Resistor to Noninverting Terminal of Op Amp. Used as reference pin in G = ½ configuration. Used as positive input in G = 2 configuration. 12 kΩ Resistor to Inverting Terminal of Op Amp. Used as negative input in G = ½ configuration. Connect to output in G = 2 configuration. 12 kΩ Resistor to Noninverting Terminal of Op Amp. Used as positive input in G = ½ configuration. Used as reference pin in G = 2 configuration. Negative Supply. 6 kΩ Resistor to Inverting Terminal of Op Amp. Connect to output in G = ½ configuration. Used as negative input in G = 2 configuration. Output. Positive Supply. No Connect. Rev. A | Page 5 of 5 AD8274 TYPICAL PERFORMANCE CHARACTERISTICS VS = ±15 V, TA = 25°C, gain = ½, difference amplifier configuration, unless otherwise noted. 20 INPUT COMMON-MODE VOLTAGE (V) 15 10 5 30 0V, +25V G=½ 20 VS = ±15V 10 –13.5V, +11.5V +13.5V, +11.5V CMR (µV/V) 0 –5 –10 –15 –20 –25 –30 –50 REPRESENTATIVE SAMPLES –30 –10 10 30 50 70 90 110 07362-106 0 –10 –13.5V, –11.5V +13.5V, –11.5V –20 0V, –25V 07362-210 130 –30 –15 –10 –5 0 5 10 15 TEMPERATURE (°C) OUTPUT VOLTAGE (V) Figure 5. CMR vs. Temperature, Normalized at 25°C, Gain = ½ Figure 8. Input Common-Mode Voltage vs. Output Voltage, Gain = ½, ±15 V Supplies 150 100 50 0 –50 –100 –150 REPRESENTATIVE SAMPLES –200 –50 –30 –10 10 30 50 70 90 110 INPUT COMMON-MODE VOLTAGE (V) 20 –3.5V, +15.8V 15 10 5 0 –5 –10 –15 –20–4 –1.0V, –4.0V +1.0, –6.0V –1.0V, +6.2V VS = ±2.5V +1.0V, +4.2V VS = ±5V G=½ +3.5V, +8.8V SYSTEM OFFSET (µV) 07362-107 +3.5V, –15.5V –2 –1 0 1 2 3 4 130 –3 TEMPERATURE (°C) OUTPUT VOLTAGE (V) Figure 6. System Offset vs. Temperature, Normalized at 25°C, Referred to Output, Gain = ½ Figure 9. Input Common-Mode Voltage vs. Output Voltage, Gain = ½, ±5 V and ±2.5 V Supplies 30 INPUT COMMON-MODE VOLTAGE (V) 20 10 25 20 15 10 5 0 –5 –10 –15 –20 –25 –15 –10 –5 –13.5V, –11.5V –13.5V, +11.5V 0V, +20.85V VS = ±15V G=2 GAIN ERROR (µV/V) +13.5V, +11.5V 0 –10 –20 –30 07362-108 +13.5V, –11.5V REPRESENTATIVE SAMPLES –50 –50 –30 –10 10 30 50 70 90 110 0V, –20.85V 0 5 10 15 130 TEMPERATURE (°C) OUTPUT VOLTAGE (V) Figure 7. Gain Error vs. Temperature, Normalized at 25°C, Gain = ½ Figure 10. Input Common-Mode Voltage vs. Output Voltage, Gain = 2, ±15 V Supplies Rev. A | Page 6 of 6 07362-111 –40 07362-110 –3.5V, –8.7V AD8274 8 INPUT COMMON-MODE VOLTAGE (V) 6 4 –1.0V, +2.7V 2 0 –2 –4 –15 –6 –8–4 +3.5V, –6.9V –3 –2 –1 0 1 2 3 4 OUTPUT VOLTAGE (V) 07362-112 –3.5V, +6.9V VS = ±5V G=2 +3.5V, +5.2V 10 G=2 5 VS = ±2.5V +1.0V, +2.2V GAIN (dB) 0 –5 G=½ –1.0V, –2.0V +1.0, –2.6V –10 –3.5V, –5.2V 1k 10k 100k 1M 10M 100M FREQUENCY(Hz) Figure 11. Input Common-Mode Voltage vs. Output Voltage, Gain = 2, ±5 V and ±2.5 V Supplies Figure 14. Gain vs. Frequency 140 POSITIVE PSRR 120 100 80 60 40 20 0 NEGATIVE PSRR 120 GAIN = 2 GAIN = ½ 80 CMRR (dB) POWER SUPPLY REJECTION (dB) 100 60 40 20 07362-021 1 10 100 1k 10k 100k 1M 100 1k 10k 100k 1M FREQUENCY (Hz) FREQUENCY (Hz) Figure 12. Power Supply Rejection Ratio vs. Frequency, Gain = ½, Referred to Output Figure 15. Common-Mode Rejection Ratio vs. Frequency, Referred to Input 32 MAXIMUM OUTPUT VOLTAGE (V p-p) 120 28 24 20 16 12 8 4 ±15V SUPPLY SHORT-CIRCUIT CURRENT (mA) 100 80 60 40 20 0 –20 –40 –60 –80 07362-006 SOURCING ±5V SUPPLY SINKING 07362-117 0 100 1k 10k 100k 1M 10M –100 –40 –20 0 20 40 60 80 100 120 FREQUENCY (Hz) TEMPERATURE (°C) Figure 13. Maximum Output Voltage vs. Frequency Figure 16. Short-Circuit Current vs. Temperature Rev. A | Page 7 of 7 07362-217 0 10 07362-007 –20 100 AD8274 +VS +125°C +85°C +25°C CL = 100pF OUTPUT VOLTAGE SWING (V) +VS – 2 –40°C +VS – 4 50mV/DIV 0 –VS + 2 +125°C NO LOAD 600Ω 2kΩ –VS + 4 07362-025 07362-009 –VS –40°C +25°C +85°C 200 1k LOAD RESISTANCE (Ω) 10k 1µs/DIV Figure 17. Output Voltage Swing vs. RL, VS = ±15 V Figure 20. Small-Signal Step Response, Gain = ½ +VS –40°C +25°C +VS – 3 OUTPUT VOLTAGE (V) +VS – 6 +125°C –VS + 6 +125°C +85°C +25°C –VS + 3 07362-026 07362-027 07362-023 –VS –40°C 0 20 40 60 80 100 50mV/DIV +85°C 1µs/DIV CURRENT (mA) Figure 18. Output Voltage vs. IOUT Figure 21. Small-Signal Pulse Response with 500 pF Capacitor Load, Gain = 2 CL = 100pF 50mV/DIV NO LOAD 600Ω 2kΩ 1µs/DIV 07362-024 50mV/DIV 1µs/DIV Figure 19. Small-Signal Step Response, Gain = 2 Figure 22. Small-Signal Pulse Response for 100 pF Capacitive Load, Gain = ½ Rev. A | Page 8 of 8 AD8274 100 90 80 70 2.5V 5V 100 90 80 70 OVERSHOOT (%) OVERSHOOT (%) 15V 18V 60 50 40 30 20 10 60 50 40 30 20 10 18V 2.5V 5V 15V 07362-037 0 20 40 60 80 100 120 140 160 180 200 0 200 400 600 800 1000 1200 CAPACITIVE LOAD (pF) CAPACITIVE LOAD (pF) Figure 23. Small-Signal Overshoot vs. Capacitive Load, Gain = ½, No Resistive Load Figure 26. Small-Signal Overshoot vs. Capacitive Load, Gain = 2, 600 Ω in Parallel with Capacitive Load 100 90 80 70 OVERSHOOT (%) 2.5V 5V 15V 18V 2V/DIV 60 50 40 30 20 0 20 40 60 80 100 120 140 160 180 200 07362-038 0 1µs/DIV CAPACITIVE LOAD (pF) Figure 24. Small-Signal Overshoot vs. Capacitive Load, Gain = ½, 600 Ω in Parallel with Capacitive Load Figure 27. Large-Signal Pulse Response, Gain = ½ 100 90 80 70 OVERSHOOT (%) 60 50 2.5V 5V 18V 15V 2V/DIV 40 30 20 10 0 200 400 600 800 1000 1200 07362-039 0 1µs/DIV CAPACITIVE LOAD (pF) Figure 25. Small-Signal Overshoot vs. Capacitive Load, Gain = 2, No Resistive Load Figure 28. Large-Signal Pulse Response, Gain = 2 Rev. A | Page 9 of 9 07362-033 07362-032 10 07362-040 0 0 AD8274 40 35 30 0.1 22kHz FILTER VOUT = 10V p-p RL = 600Ω 0.01 SLEW RATE (V/µS) +SR –SR 20 15 10 5 THDN + N (%) 25 0.001 GAIN = 2 GAIN = ½ TEMPERATURE (°C) 07362-010 –20 0 20 40 60 80 100 120 100 1k FREQUENCY (Hz) 10k 100k Figure 29. Slew Rate vs. Temperature Figure 32. THD + N vs. Frequency, Filter = 22k Hz 10k 0.1 VOUT = 10V p-p VOLTAGE NOISE DENSITY (nV/√Hz) 1k THD + N (%) 0.01 100 GAIN = 2 0.001 GAIN = 2 GAIN = ½ 10 1 10 100 1k 10k 100k FREQUENCY (Hz) GAIN = ½ 07362-034 100 1k FREQUENCY (Hz) 10k 100k Figure 30. Voltage Noise Density vs. Frequency, Referred to Output Figure 33. THD + N vs. Frequency, Filter = 120 kHz 1 GAIN = ½ f = 1kHz G=2 0.1 THD + N (%) 1µV/DIV 0.01 RL = 2kΩ, 100Ω G=½ 0.001 RL = 600Ω 07362-035 1s/DIV 0 5 10 15 OUTPUT AMPLITUDE (dBu) 20 25 Figure 31. 0.1 Hz to 10 Hz Voltage Noise, RTO Figure 34. THD + N vs. Output Amplitude, G = ½ Rev. A | Page 10 of 10 07362-136 0.0001 07362-135 0.0001 10 07362-131 0 –40 0.0001 10 AD8274 1 GAIN = 2 f = 1kHz 0.1 AMPLITUDE (% OF FUNDAMENTAL) 0.1 GAIN = 2 VOUT = 10V p-p 0.01 THD + N (%) 0.01 RL = 600Ω RL = 2kΩ RL = 100kΩ 0.001 THIRD HARMONIC ALL LOADS 0.001 0.0001 SECOND HARMONIC R L = 600Ω SECOND HARMONIC R L = 100kΩ, 2kΩ 100 1k FREQUENCY (Hz) 10k 100k 07362-139 07362-137 0.0001 0 5 10 15 OUTPUT AMPLITUDE (dBu) 20 25 0.00001 10 Figure 35. THD + N vs. Output Amplitude, G = 2 Figure 37. Harmonic Distortion Products vs. Frequency, G = 2 0.1 GAIN = ½ VOUT = 10V p-p AMPLITUDE (% OF FUNDAMENTAL) 0.01 0.001 THIRD HARMONIC ALL LOADS 0.0001 SECOND HARMONIC R L = 600Ω SECOND HARMONIC R L = 100kΩ, 2kΩ 100 1k FREQUENCY (Hz) 10k 100k 07362-138 0.00001 10 Figure 36. Harmonic Distortion Products vs. Frequency, G = ½ Rev. A | Page 11 of 11 AD8274 THEORY OF OPERATION +VS 7 2 DRIVING THE AD8274 6kΩ 5 12kΩ 6 3 12kΩ 4 6kΩ 1 07362-001 The AD8274 is easy to drive, with all configurations presenting at least several kilohms (kΩ) of input resistance. The AD8274 should be driven with a low impedance source: for example, another amplifier. The gain accuracy and common-mode rejection of the AD8274 depend on the matching of its resistors. Even source resistance of a few ohms can have a substantial effect on these specifications. –VS POWER SUPPLIES A stable dc voltage should be used to power the AD8274. Noise on the supply pins can adversely affect performance. A bypass capacitor of 0.1 μF should be placed between each supply pin and ground, as close as possible to each supply pin. A tantalum capacitor of 10 μF should also be used between each supply and ground. It can be farther away from the supply pins and, typically, it can be shared by other precision integrated circuits. The AD8274 is specified at ±15 V, but it can be used with unbalanced supplies, as well. For example, −VS = 0 V, +VS = 20 V. The difference between the two supplies must be kept below 36 V. Figure 38. Functional Block Diagram CIRCUIT INFORMATION The AD8274 consists of a high precision, low distortion op amp and four trimmed resistors. These resistors can be connected to make a wide variety of amplifier configurations, including difference, noninverting, and inverting configurations. Using the on-chip resistors of the AD8274 provides the designer with several advantages over a discrete design. DC Performance Much of the dc performance of op amp circuits depends on the accuracy of the surrounding resistors. The resistors on the AD8274 are laid out to be tightly matched. The resistors of each part are laser trimmed and tested for their matching accuracy. Because of this trimming and testing, the AD8274 can guarantee high accuracy for specifications such as gain drift, common-mode rejection, and gain error. INPUT VOLTAGE RANGE The AD8274 can measure voltages beyond the rails. For the G = ½ and G = 2 difference amplifier configurations, see the input voltage range in Table 2 for specifications. The AD8274 is able to measure beyond the rail because the internal resistors divide down the voltage before it reaches the internal op amp. Figure 39 shows an example of how the voltage division works in the difference amplifier configuration. For the AD8274 to measure correctly, the input voltages at the internal op amp must stay within 1.5 V of either supply rail. R2 (V ) R1 + R2 IN+ R4 R3 R1 R2 R2 (V ) R1 + R2 IN+ 07362-061 AC Performance Because feature size is much smaller in an integrated circuit than on a printed circuit board (PCB), the corresponding parasitics are also smaller. The smaller feature size helps the ac performance of the AD8274. For example, the positive and negative input terminals of the AD8274 op amp are not pinned out intentionally. By not connecting these nodes to the traces on the PCB, the capacitance remains low, resulting in both improved loop stability and common-mode rejection over frequency. Production Costs Because one part, rather than several, is placed on the PCB, the board can be built more quickly. Figure 39. Voltage Division in the Difference Amplifier Configuration Size The AD8274 fits a precision op amp and four resistors in one 8-lead MSOP or SOIC package. For best long-term reliability of the part, voltages at any of the part’s inputs (Pin 1, Pin 2, Pin 3, or Pin 5) should stay within +VS – 40 V to −VS + 40 V. For example, on ±10 V supplies, input voltages should not exceed ±30 V. Rev. A | Page 12 of 12 AD8274 CONFIGURATIONS The AD8274 can be configured in several ways; see Figure 40 to Figure 47. Because these configurations rely on the internal, matched resistors, all of these configurations have excellent gain accuracy and gain drift. Note that the AD8274 internal op amp is stable for noise gains of 1.5 and higher, so the AD8274 should not be placed in a unity-gain follower configuration. –IN 2 12kΩ 6kΩ 5 6 OUT 2 12kΩ 6kΩ 5 6 OUT +IN 3 12kΩ 6kΩ 1 07362-012 +IN 3 12kΩ 6kΩ 1 07362-015 VOUT = ½ (VIN+ − VIN−) VOUT = ½ VIN Figure 40. Difference Amplifier, G = ½ Figure 44. Noninverting Amplifier, G = ½ –IN 5 6kΩ 12kΩ 2 6 OUT 5 6kΩ 12kΩ 2 6 OUT +IN 1 07362-016 6kΩ 12kΩ 3 +IN 1 6kΩ 12kΩ 3 07362-019 VOUT = 2 (VIN+ − VIN−) VOUT = 2 VIN Figure 41. Difference Amplifier, G = 2 Figure 45. Noninverting Amplifier, G = 2 –IN 2 12kΩ 6kΩ 5 6 OUT 2 12kΩ 6kΩ 5 6 OUT 1 6kΩ 1 07362-013 6kΩ 07362-014 3 12kΩ +IN 3 12kΩ VOUT = –½ VIN VOUT = 1½ VIN Figure 42. Inverting Amplifier, G = −½ Figure 46. Noninverting Amplifier, G = 1.5 –IN 5 6kΩ 12kΩ 2 6 OUT 5 6kΩ 12kΩ 2 6 OUT 1 12kΩ 3 6kΩ 3 12kΩ +IN 07362-017 1 6kΩ 07362-018 VOUT = –2 VIN VOUT = 3 VIN Figure 43. Inverting Amplifier, G = −2 Figure 47. Noninverting Amplifier, G = 3 Rev. A | Page 13 of 13 AD8274 DRIVING CABLING Because the AD8274 can drive large voltages at high output currents and slew rates, it makes an excellent cable driver. It is good practice to put a small value resistor between the AD8274 output and cable, since capacitance in the cable can cause peaking or instability in the output response. A resistance of 20 Ω or higher is recommended. AD8274 R ≥ 20Ω Figure 48. Driving Cabling 06979-060 Rev. A | Page 14 of 14 AD8274 OUTLINE DIMENSIONS 5.00 (0.1968) 4.80 (0.1890) 4.00 (0.1574) 3.80 (0.1497) 8 1 5 4 6.20 (0.2441) 5.80 (0.2284) 1.27 (0.0500) BSC 0.25 (0.0098) 0.10 (0.0040) COPLANARITY 0.10 SEATING PLANE 1.75 (0.0688) 1.35 (0.0532) 0.50 (0.0196) 0.25 (0.0099) 8° 0° 0.25 (0.0098) 0.17 (0.0067) 1.27 (0.0500) 0.40 (0.0157) 45° 0.51 (0.0201) 0.31 (0.0122) COMPLIANT TO JEDEC STANDARDS MS-012-A A CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 49. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) 3.20 3.00 2.80 3.20 3.00 2.80 PIN 1 8 5 1 5.15 4.90 4.65 4 0.65 BSC 0.95 0.85 0.75 0.15 0.00 0.38 0.22 SEATING PLANE 1.10 MAX 8° 0° 0.80 0.60 0.40 0.23 0.08 COPLANARITY 0.10 COMPLIANT TO JEDEC STANDARDS MO-187-AA Figure 50. 8-Lead Mini Small Outline Package [MSOP] (RM-8) Dimensions shown in millimeters ORDERING GUIDE Model AD8274ARZ 1 AD8274ARZ-R71 AD8274ARZ-RL1 AD8274ARMZ1 AD8274ARMZ-R71 AD8274ARMZ-RL1 1 Temperature Range −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C Package Description 8-Lead SOIC_N 8-Lead SOIC_N, 7" Tape and Reel 8-Lead SOIC_N, 13" Tape and Reel 8-Lead MSOP 8-Lead MSOP, 7" Tape and Reel 8-Lead MSOP, 13" Tape and Reel Package Option R-8 R-8 R-8 RM-8 RM-8 RM-8 012407-A Branding Y1B Y1B Y1B Z = RoHS Compliant Part. Rev. A | Page 15 of 15 AD8274 NOTES ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07362-0-12/08(A) Rev. A | Page 16 of 16