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Low Cost, Low Power Video Op Amp AD818 FEATURES Low Cost Excellent Video Performance 55 MHz 0.1 dB Bandwidth (Gain = +2) 0.01% and 0.05؇ Differential Gain and Phase Errors High Speed 130 MHz Bandwidth (3 dB, G = +2) 100 MHz Bandwidth (3 dB, G+ = –1) 500 V/␮s Slew Rate 80 ns Settling Time to 0.01% (VO = 10 V Step) High Output Drive Capability 50 mA Minimum Output Current Ideal for Driving Back Terminated Cables Flexible Power Supply Specified for Single (+5 V) and Dual (؎5 V to ؎15 V) Power Supplies Low Power: 7.5 mA Max Supply Current Available in 8-Lead SOIC and 8-Lead PDIP GENERAL DESCRIPTION The AD818 is a low cost video op amp optimized for use in video applications that require gains equal to or greater than +2 or –1. The AD818’s low differential gain and phase errors, single supply functionality, low power, and high output drive make it ideal for cable driving applications such as video cameras and professional video equipment. With video specs like 0.1 dB flatness to 55 MHz and low differential gain and phase errors of 0.01% and 0.05∞, along with 50 mA of output current, the AD818 is an excellent choice for +15V 0.01␮F 2.2␮F VIN 1k⍀ REV. D AD818 0.1␮F RBT 75⍀ 75⍀ 2.2␮F RT 75⍀ –15V 1k⍀ Figure 1. Video Line Driver CONNECTION DIAGRAM 8-Lead Plastic Mini-DIP (N) and SOIC (R) Packages NULL 1 –IN 2 +IN 3 AD818 8 NULL 7 +VS 6 OUTPUT –VS 4 TOP VIEW 5 NC NC = NO CONNECT any video application. The 130 MHz 3 dB bandwidth (G = +2) and 500 V/ms slew rate make the AD818 useful in many high speed applications including video monitors, CATV, color copiers, image scanners, and fax machines. The AD818 is fully specified for operation with a single +5 V power supply and with dual supplies from ± 5 V to ± 15 V. This power supply flexibility, coupled with a very low supply current of 7.5 mA and excellent ac characteristics under all power supply conditions, make the AD818 the ideal choice for many demanding yet power sensitive applications. The AD818 is a voltage feedback op amp and excels as a gain stage in high speed and video systems (gain ≥ 2, or gain £ –1). It achieves a settling time of 45 ns to 0.1%, with a low input offset voltage of 2 mV max. The AD818 is available in low cost, small 8-lead PDIP and SOIC packages. 0.02 DIFF GAIN 0.01 DIFFERENTIAL PHASE (Degrees) DIFFERENTIAL GAIN (%) 0.06 0.00 0.05 DIFF PHASE 0.04 0.03 5 10 15 SUPPLY VOLTAGE (؎V) Figure 2. Differential Gain and Phase vs. Supply 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. 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 companies. 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 ©2010 Analog Devices, Inc. All rights reserved. AD818* PRODUCT PAGE QUICK LINKS Last Content Update: 02/23/2017 COMPARABLE PARTS View a parametric search of comparable parts. EVALUATION KITS • Universal Evaluation Board for Single High Speed Operational Amplifiers DOCUMENTATION Application Notes • AN-356: User's Guide to Applying and Measuring Operational Amplifier Specifications • AN-402: Replacing Output Clamping Op Amps with Input Clamping Amps • AN-417: Fast Rail-to-Rail Operational Amplifiers Ease Design Constraints in Low Voltage High Speed Systems • AN-581: Biasing and Decoupling Op Amps in Single Supply Applications • AN-649: Using the Analog Devices Active Filter Design Tool Data Sheet • AD818: Low Cost, Low Power Video Op Amp Data Sheet User Guides • UG-135: Evaluation Board for Single, High Speed Operational Amplifiers (8-Lead SOIC and Exposed Paddle) TOOLS AND SIMULATIONS • Analog Filter Wizard • Analog Photodiode Wizard • Power Dissipation vs Die Temp • VRMS/dBm/dBu/dBV calculators • AD818 SPICE Macro-Model REFERENCE MATERIALS Product Selection Guide • High Speed Amplifiers Selection Table Tutorials • MT-032: Ideal Voltage Feedback (VFB) Op Amp • MT-033: Voltage Feedback Op Amp Gain and Bandwidth • MT-047: Op Amp Noise • MT-048: Op Amp Noise Relationships: 1/f Noise, RMS Noise, and Equivalent Noise Bandwidth • MT-049: Op Amp Total Output Noise Calculations for Single-Pole System • MT-050: Op Amp Total Output Noise Calculations for Second-Order System • MT-052: Op Amp Noise Figure: Don't Be Misled • MT-056: High Speed Voltage Feedback Op Amps • MT-058: Effects of Feedback Capacitance on VFB and CFB Op Amps • MT-059: Compensating for the Effects of Input Capacitance on VFB and CFB Op Amps Used in Current-toVoltage Converters • MT-060: Choosing Between Voltage Feedback and Current Feedback Op Amps DESIGN RESOURCES • AD818 Material Declaration • PCN-PDN Information • Quality And Reliability • Symbols and Footprints DISCUSSIONS View all AD818 EngineerZone Discussions. SAMPLE AND BUY Visit the product page to see pricing options. TECHNICAL SUPPORT Submit a technical question or find your regional support number. DOCUMENT FEEDBACK Submit feedback for this data sheet. This page is dynamically generated by Analog Devices, Inc., and inserted into this data sheet. A dynamic change to the content on this page will not trigger a change to either the revision number or the content of the product data sheet. This dynamic page may be frequently modified. AD818–SPECIFICATIONS (@ TA = 25؇C, unless otherwise noted.) Parameter DYNAMIC PERFORMANCE –3 dB Bandwidth Bandwidth for 0.1 dB Flatness Full Power Bandwidth* Slew Rate Settling Time to 0.1% Settling Time to 0.01% Total Harmonic Distortion Differential Gain Error (RL = 150 W) Differential Phase Error (RL = 150 W) Cap Load Drive INPUT OFFSET VOLTAGE Offset Drift INPUT BIAS CURRENT INPUT OFFSET CURRENT Offset Current Drift OPEN-LOOP GAIN COMMON-MODE REJECTION Conditions VS Gain = +2 Gain = –1 Gain = +2 CC = 2 pF Gain = –1 CC = 2 pF VOUT = 5 V p-p RLOAD = 500 W VOUT = 20 V p-p RLOAD = 1 kW RLOAD = 1 kW Gain = –1 –2.5 V to +2.5 V 0 V–10 V Step, AV = –1 –2.5 V to +2.5 V 0 V–10 V Step, AV = –1 FC = 1 MHz NTSC Gain = +2 NTSC Gain = +2 ±5 V ± 15 V 0 V, +5 V ±5 V ± 15 V 0 V, +5 V ±5 V ± 15 V 0 V, +5 V ±5 V ± 15 V 0 V, +5 V ±5 V ± 15 V ±5 V ± 15 V 0 V, +5 V ±5 V ± 15 V ±5 V ± 15 V ± 15 V ± 15 V ±5 V 0 V, +5 V ± 15 V ±5 V 0 V, +5 V TMIN to TMAX TMIN TMAX TMIN to TMAX VOUT = ± 2.5 V RLOAD = 500 W TMIN to TMAX RLOAD = 150 W VOUT = ± 10 V RLOAD = 1 kW TMIN to TMAX VOUT = ± 7.5 V RLOAD = 150 W (50 mA Output) VCM = ± 2.5 V VCM = ± 12 V TMIN to TMAX ± 5 V to ± 15 V ± 5 V, ± 15 V ± 5 V, ± 15 V ±5 V ± 15 V ± 15 V ±5 V ± 15 V ± 15 V AD818A Min Typ Max 70 95 100 130 40 55 50 70 70 100 30 50 20 43 40 55 10 18 18 34 40 72 10 19 25.5 8.0 350 400 450 500 250 300 45 45 80 80 63 0.005 0.01 0.01 0.02 0.08 0.045 0.09 0.06 0.09 0.1 10 0.5 2 3 10 3.3 6.6 10 4.4 25 300 500 0.3 3 5 2 2 4 6 9 3 3 5 82 100 86 120 84 100 Unit MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz MHz V/ms V/ms V/ms ns ns ns ns dB % % % Degrees Degrees Degrees pF mV mV mV/∞C mA mA mA nA nA nA/∞C V/mV V/mV V/mV V/mV V/mV V/mV dB dB dB –2– REV. D Parameter POWER SUPPLY REJECTION INPUT VOLTAGE NOISE INPUT CURRENT NOISE INPUT COMMON-MODE VOLTAGE RANGE Conditions VS = ± 5 V to ± 15 V TMIN to TMAX f = 10 kHz f = 10 kHz OUTPUT VOLTAGE SWING Output Current RLOAD = 500 W RLOAD = 150 W RLOAD = 1 kW RLOAD = 500 W RLOAD = 500 W Short-Circuit Current INPUT RESISTANCE INPUT CAPACITANCE OUTPUT RESISTANCE POWER SUPPLY Operating Range Quiescent Current Open Loop Dual Supply Single Supply TMIN to TMAX TMIN to TMAX *Full power bandwidth = slew rate/(2p VPEAK). Specifications subject to change without notice. VS ± 5 V, ± 15 V ± 5 V, ± 15 V ±5 V ± 15 V 0 V, +5 V ±5 V ±5 V ± 15 V ± 15 V 0 V, +5 V ± 15 V ±5 V 0 V, +5 V ± 15 V ±5 V ±5 V ± 15 V ± 15 V AD818 AD818A Min Typ Max 80 90 80 10 1.5 Unit dB dB nV/÷Hz pA/÷Hz +3.8 +4.3 V –2.7 –3.4 V +13 +14.3 V –12 –13.4 V +3.8 +4.3 V +1.2 +0.9 V 3.3 3.8 ±V 3.2 3.6 ±V 13.3 13.7 ±V 12.8 13.4 ±V 1.5, 3.5 V 50 mA 50 mA 30 mA 90 mA 300 kW 1.5 pF 8 W ± 2.5 ± 18 V +5 +36 V 7.0 7.5 mA 7.5 mA 7.5 mA 7.0 7.5 mA REV. D –3– AD818 ABSOLUTE MAXIMUM RATINGS1 Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 18 V Internal Power Dissipation2 Plastic (N) . . . . . . . . . . . . . . . . . . . . . . See Derating Curves Small Outline (R) . . . . . . . . . . . . . . . . . See Derating Curves Input Voltage (Common Mode) . . . . . . . . . . . . . . . . . . . . ± VS Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . ± 6 V Output Short-Circuit Duration . . . . . . . . See Derating Curves Storage Temperature Range (N, R) . . . . . . . . –65∞C to +125∞C Operating Temperature Range . . . . . . . . . . . . –40∞C to +85∞C Lead Temperature Range (Soldering 10 sec) . . . . . . . . . 300∞C NOTES 1Stresses 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. 2Specification is for device in free air: 8-lead plastic package, ␪JA = 90∞C/W; 8-lead SOIC package, ␪JA = 155∞C/W. MAXIMUM POWER DISSIPATION (W) 2.0 TJ = 150 C 8-LEAD MINI-DIP PACKAGE 1.5 1.0 0.5 8-LEAD SOIC PACKAGE 0 –50 –40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 AMBIENT TEMPERATURE (؇C) Figure 3. Maximum Power Dissipation vs. Temperature for Different Package Types CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD818 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. METALLIZATION PHOTOGRAPH Dimensions shown in inches and (mm) OFFSET OFFSET NULL NULL +VS 1 8 7 –INPUT 2 +INPUT 3 4 –VS 0.0559 (1.42) –4– 0.0523 (1.33) 6 OUTPUT REV. D Typical Performance Characteristics–AD818 20 20 OUTPUT VOLTAGE SWING (؎V) INPUT COMMON-MODE RANGE (؎V) 15 +VCM 10 –VCM 5 15 RL = 500⍀ 10 RL = 150⍀ 5 0 0 5 10 15 20 SUPPLY VOLTAGE (؎V) TPC 1. Common-Mode Voltage Range vs. Supply 30 OUTPUT VOLTAGE SWING (V p-p) 25 VS = ؎15V 20 15 10 VS = ؎5V 5 0 10 100 1k 10k LOAD RESISTANCE (⍀) TPC 2. Output Voltage Swing vs. Load Resistance 600 500 0 0 5 10 15 20 SUPPLY VOLTAGE (؎V) TPC 4. Output Voltage Swing vs. Supply 8.0 QUIESCENT SUPPLY CURRENT (mA) 7.5 +85؇C +25؇C 7.0 –40؇C 6.5 6.0 0 5 10 15 20 SUPPLY VOLTAGE (؎V) TPC 5. Quiescent Supply Current vs. Supply Voltage 100 10 CLOSED-LOOP OUTPUT IMPEDANCE (⍀) SLEW RATE (V/␮s) 400 1 300 0.1 200 0 5 10 15 20 SUPPLY VOLTAGE (؎V) TPC 3. Slew Rate vs. Supply Voltage 0.01 1k 10k 100k 1M 10M 100M FREQUENCY (Hz) TPC 6. Closed-Loop Output Impedance vs. Frequency REV. D –5– PHASE MARGIN (Degrees) AD818 7 6 INPUT BIAS CURRENT (␮A) 5 4 3 2 1 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE (؇C) TPC 7. Input Bias Current vs. Temperature 70 95 PHASE MARGIN 60 85 PHASE MARGIN (Degrees) 50 75 GAIN/BANDWIDTH 40 65 30 –60 –40 –20 0 20 40 60 80 TEMPERATURE (؇C) 55 100 120 140 TPC 8. –3 dB Bandwidth and Phase Margin vs. Temperature, Gain = +2 OPEN-LOOP GAIN (V/mV) 9 ؎15V 8 7 ؎5V 6 5 4 3 100 1k 10k LOAD RESISTANCE (⍀) TPC 9. Open-Loop Gain vs. Load Resistance –3dB BANDWIDTH (MHz) OPEN-LOOP GAIN (dB) SHORT CIRCUIT CURRENT (mA) 130 110 SOURCE CURRENT 90 SINK CURRENT 70 50 30 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE (؇C) TPC 10. Short-Circuit Current vs. Temperature 100 100 PHASE ؎5V OR ؎15V SUPPLIES 80 80 ؎15V SUPPLIES 60 RL = 1k⍀ 60 40 40 ؎5V SUPPLIES RL = 1k⍀ 20 20 0 0 –20 1k 10k 100k 1M 10M 100M 1G FREQUENCY (Hz) TPC 11. Open-Loop Gain and Phase Margin vs. Frequency PSR (dB) 100 90 80 +SUPPLY 70 60 –SUPPLY 50 40 30 20 10 100 1k 10k 100k 1M 10M 100M FREQUENCY (Hz) TPC 12. Power Supply Rejection vs. Frequency –6– REV. D 120 100 CMR (dB) 80 60 40 1k 10k 100k 1M 10M FREQUENCY (Hz) TPC 13. Common-Mode Rejection vs. Frequency OUTPUT SWING FROM 0 TO ؎V (V) 10 8 6 4 1% 2 0.1% 0.01% 0 –2 1% –4 0.1% 0.01% –6 –8 –10 0 20 40 60 80 100 120 140 160 SETTLING TIME (ns) TPC 14. Output Swing and Error vs. Settling Time INPUT VOLTAGE NOISE (nV/ Hz) 50 40 30 20 10 0 1 10 100 1k 10k 100k 1M 10M FREQUENCY (Hz) TPC 15. Input Voltage Noise Spectral Density vs. Frequency SLEW RATE (V/␮s) HARMONIC DISTORTION (dB) OUTPUT VOLTAGE (V p-p) AD818 30 RL = 1k⍀ 20 RL = 150⍀ 10 0 100k 1M 10M FREQUENCY (Hz) 100M TPC 16. Output Voltage vs. Frequency –40 RL = 150⍀ 2V p-p –50 –60 –70 SECOND HARMONIC –80 THIRD HARMONIC –90 –100 100 1k 10k 100k 1M 10M FREQUENCY (Hz) TPC 17. Harmonic Distortion vs. Frequency 650 550 450 350 250 –60 –40 –20 0 20 40 60 80 100 120 140 TEMPERATURE (؇C) TPC 18. Slew Rate vs. Temperature REV. D –7– AD818 DIFF GAIN 0.02 0.01 DIFFERENTIAL GAIN (%) DIFFERENTIAL PHASE (Degrees) 0.06 0.00 0.05 DIFF PHASE 0.04 0.03 5 10 15 SUPPLY VOLTAGE (؎V) TPC 19. Differential Gain and Phase vs. Supply Voltage CF 1k⍀ +VS 3.3␮F HP PULSE (LS) VIN 1k⍀ OR FUNCTION (SS) GENERATOR 50⍀ 0.01␮F AD818 VOUT TEKTRONIX P6201 FET PROBE TEKTRONIX 7A24 PREAMP 0.01␮F RL 3.3␮F –VS TPC 22. Inverting Amplifier Connection 0.1dB 10 VS CC FLATNESS 9 ؎15V 2pF 55MHz ؎5V 1pF 43MHz 8 +5V 1pF 18MHz 7 CC 1k⍀ VIN 1k⍀ AD818 VOUT 150⍀ GAIN (dB) 6 5 ؎5V ؎15V 4 3 +5V 2 1 1M 10M 100M 1G FREQUENCY (Hz) TPC 20. Closed-Loop Gain vs. Frequency (G = +2) 10 8 VS 0.1dB FLATNESS 6 ؎15V 72MHz ؎5V 34MHz 4 +5V 19MHz 2 2pF 1k⍀ VIN 1k⍀ AD818 VOUT 150⍀ GAIN (dB) 0 –2 +5V ؎15V –4 –6 ؎5V –8 –10 1M 10M 100M 1G FREQUENCY (Hz) TPC 21. Closed-Loop Gain vs. Frequency (G = –1) 2V 50ns 100 90 10 0% 2V TPC 23. Inverter Large Signal Pulse Response; VS = ±5 V, CF = 1 pF, RL = 1 kW 200mV 100 90 10ns 10 0% 200mV TPC 24. Inverter Small Signal Pulse Response; VS = ±5 V, CF = 1 pF, RL = 150 W –8– REV. D 5V 100 90 50ns 10 0% 5V TPC 25. Inverter Large Signal Pulse Response; VS = ±15 V, CF = 1 pF, RL = 1 kW 200mV 100 90 10ns 1k⍀ CF 1k⍀ +VS 3.3␮F AD818 0.01␮F HP PULSE (LS) VIN 100⍀ OR FUNCTION (SS) GENERATOR 50⍀ AD818 VOUT TEKTRONIX P6201 FET PROBE TEKTRONIX 7A24 PREAMP 0.01␮F RL 3.3␮F –VS TPC 28. Noninverting Amplifier Connection 1V 100 90 50ns 10 0% 200mV TPC 26. Inverter Small Signal Pulse Response; VS = ±15 V, CF = 1 pF, RL = 150 W 200mV 100 90 10ns 10 0% 2V TPC 29. Noninverting Large Signal Pulse Response; VS = ±5 V, CF = 1 pF, RL = 1 kW 100mV 100 90 10ns 10 0% 200mV TPC 27. Inverter Small Signal Pulse Response; VS = ±5 V, CF = 0 pF, RL = 150 W 10 0% 200mV TPC 30. Noninverting Small Signal Pulse Response; VS = ±5 V, CF = 1 pF, RL = 150 W REV. D –9– AD818 5V 100 90 50ns 100mV 100 90 10ns 10 0% 5V TPC 31. Noninverting Large Signal Pulse Response; VS = ±15 V, CF = 1 pF, RL = 1 kW 100mV 100 90 10ns 10 0% 200mV TPC 33. Noninverting Small Signal Pulse Response; VS = ±5 V, CF = 0 pF, RL = 150 W 10 0% 200mV TPC 32. Noninverting Small Signal Pulse Response; VS = ±15 V, CF = 1 pF, RL = 150 W –10– REV. D AD818 +VS may result in peaking. A small capacitance (1 pF–5 pF) may be used in parallel with the feedback resistor to neutralize this effect. Power supply leads should be bypassed to ground as close as possible to the amplifier pins. Ceramic disc capacitors of 0.1 mF OUTPUT are recommended. –IN +VS +IN –VS NULL 1 NULL 8 Figure 4. AD818 Simplified Schematic THEORY OF OPERATION The AD818 is a low cost video operational amplifier designed to excel in high performance, high output current video applications. The AD818 (Figure 4) consists of a degenerated NPN differential pair driving matched PNPs in a folded-cascode gain stage. The output buffer stage employs emitter followers in a class AB amplifier that delivers the necessary current to the load, while maintaining low levels of distortion. The AD818 will drive terminated cables and capacitive loads of 10 pF or less. As the closed-loop gain is increased, the AD818 will drive heavier capacitive loads without oscillating. INPUT CONSIDERATIONS An input protection resistor (RIN in TPC 28) is required in circuits where the input to the AD818 will be subjected to transients of continuous overload voltages exceeding the ± 6 V maximum differential limit. This resistor provides protection for the input transistors by limiting their maximum base current. For high performance circuits, it is recommended that a “balancing” resistor be used to reduce the offset errors caused by bias current flowing through the input and feedback resistors. The balancing resistor equals the parallel combination of RIN and RF and thus provides a matched impedance at each input terminal. The offset voltage error will then be reduced by more than an order of magnitude. GROUNDING AND BYPASSING When designing high frequency circuits, some special precautions are in order. Circuits must be built with short interconnect leads. When wiring components, care should be taken to provide a low resistance, low inductance path to ground. Sockets should be avoided, since their increased interlead capacitance can degrade circuit bandwidth. Feedback resistors should be of low enough value (£1 kW) to ensure that the time constant formed with the inherent stray capacitance at the amplifier’s summing junction will not limit performance. This parasitic capacitance, along with the parallel resistance of RFʈRIN, forms a pole in the loop transmission, which AD818 10k⍀ –VS VOS ADJUST Figure 5. Offset Null Configuration OFFSET NULLING The input offset voltage of the AD818 is inherently very low. However, if additional nulling is required, the circuit shown in Figure 5 can be used. The null range of the AD818 in this configuration is ± 10 mV. SINGLE SUPPLY OPERATION Another exciting feature of the AD818 is its ability to perform well in a single supply configuration. The AD818 is ideally suited for applications that require low power dissipation and high output current. Referring to Figure 6, careful consideration should be given to the proper selection of component values. The choices for this particular circuit are: R1 + R3ʈR2 combine with C1 to form a low frequency corner of approximately 10 kHz. C4 was inserted in series with R4 to maintain amplifier stability at high frequency. Combining R3 with C2 forms a low-pass filter with a corner frequency of approximately 500 Hz. This is needed to maintain amplifier PSRR, since the supply is connected to VIN through the input divider. The values for R2 and C2 were chosen to demonstrate the AD818’s exceptional output drive capability. In this configuration, the output is centered around 2.5 V. In order to eliminate the static dc current associated with this level, C3 was inserted in series with R L. VS R3 100⍀ C2 3.3␮F R4 1k⍀ C4 0.001␮F C1 0.01␮F VIN R1 3.3k⍀ R2 3.3k⍀ 1k⍀ 3.3␮F SELECT C1, R1, R2 FOR DESIRED LOW FREQUENCY CORNER. 0.01␮F AD818 VOUT C3 0.1␮F RL 150⍀ Figure 6. Single-Supply Amplifier Configuration REV. D –11– AD818 ERROR SIGNAL OUTPUT ERROR AMPLIFIER VERROR OUTPUT ؋ 10 2؋ HP2835 AD829 2؋ HP2835 100⍀ 0.47␮F 1M⍀ 15pF SHORT, DIRECT CONNECTION TO TEKTRONIX TYPE 11402 OSCILLOSCOPE PREAMP INPUT SECTION 0 TO ؎10V POWER SUPPLY TTL LEVEL SIGNAL GENERATOR 50Hz OUTPUT DIGITAL GROUND ANALOG GROUND EI&S DL1A05GM MERCURY RELAY 7, 8 1, 14 50⍀ COAX CABLE NULL ADJUST FALSE SUMMING NODE 1k⍀ 1k⍀ 100⍀ 500⍀ 500⍀ 50⍀ 5pF–18pF AD818 2.2␮F 0.01␮F 2.2␮F –VS +VS 0.01␮F 0.47␮F 1.9k⍀ –VS +VS 0.01␮F 100⍀ NOTE USE CIRCUIT BOARD WITH GROUND PLANE DEVICE UNDER TEST 0.01␮F 10pF SCOPE PROBE CAPACITANCE TEKTRONIX P6201 FET PROBE TO TEKTRONIX TYPE 11402 OSCILLOSCOPE PREAMP INPUT SECTION Figure 7. Settling Time Test Circuit AD818 SETTLING TIME Settling time primarily comprises two regions. The first is the slew time in which the amplifier is overdriven, where the output voltage rate of change is at its maximum. The second is the linear time period required for the amplifier to settle to within a specified percentage of the final value. Measuring the rapid settling time of the AD818 (45 ns to 0.1% and 80 ns to 0.01%—10 V step) requires applying an input pulse with a very fast edge and an extremely flat top. With the AD818 configured in a gain of –1, a clamped false summing junction responds when the output error is within the sum of two diode voltages (approximately 1 V). The signal is then amplified 20 times by a clamped amplifier whose output is connected directly to a sampling oscilloscope. A High Performance Video Line Driver The buffer circuit shown in Figure 8 will drive a back-terminated 75 W video line to standard video levels (1 V p-p) with 0.1 dB gain flatness to 55 MHz with only 0.05∞ and 0.01% differential phase and gain at the 3.58 MHz NTSC subcarrier frequency. This level of performance, which meets the requirements for high definition video displays and test equipment, is achieved using only 7 mA quiescent current. VIN RT 75⍀ +15V 0.01␮F AD818 1k⍀ 0.01␮F –15V 1k⍀ 2.2␮F RBT 75⍀ 75⍀ 2.2␮F RT 75⍀ Figure 8. Video Line Driver –12– REV. D DIFFERENTIAL LINE RECEIVER The differential receiver circuit of Figure 9 is useful for many applications—from audio to video. It allows extraction of a low level signal in the presence of common-mode noise, as shown in Figure 10. 1k⍀ VB 2pF 1k⍀ +5V 0.01␮F 2.2␮F DIFFERENTIAL INPUT 1k⍀ VA AD818 VOUT 0.01␮F –5V 1k⍀ 2pF 2.2␮F OUTPUT Figure 9. Differential Line Receiver 100 90 1V VA 20ns AD818 A HIGH SPEED, 3-OP AMP IN AMP The circuit of Figure 11 uses three high speed op amps: two AD818s and an AD817. This high speed circuit lends itself well to CCD imaging and other video speed applications. It has the optional flexibility of both dc and ac trims for common-mode rejection, plus the ability to adjust for minimum settling time. +15V 10␮F COMMON 10␮F –15V EACH AMPLIFIER +VS 0.1␮F 1␮F PIN 7 EACH AMPLIFIER 0.1␮F 0.1␮F 1␮F –VS 0.1␮F PIN 4 EACH AMPLIFIER –VIN A1 AD818 1k⍀ 5pF 2pF RG 5pF 1k⍀ A2 AD818 +VIN SETTLING 2pF–8pF TIME AC CMR ADJUST 1k⍀ 1k⍀ A3 1k⍀ AD818 3pF 970⍀ 50⍀ DC CMR ADJUST VOUT RL 2k⍀ 2V 10 0% OUTPUT Figure 10. Performance of Line Receiver, RL = 150 W, G = +2 BANDWIDTH, SETTLING TIME, AND TOTAL HARMONIC DISTORTION VS. GAIN GAIN 3 10 100 SMALL CADJ SIGNAL RG (pF) BANDWIDTH 1k⍀ 2–8 222⍀ 2–8 20⍀ 2–8 14.7MHz 4.5MHz 960kHz SETTLING TIME TO 0.1% 200ns 370ns 2.5␮s THD + NOISE BELOW INPUT LEVEL @ 10kHz 82dB 81dB 71dB Figure 11. High Speed 3-Op Amp In Amp REV. D –13– AD818 OUTLINE DIMENSIONS 0.400 (10.16) 0.365 (9.27) 0.355 (9.02) 8 5 1 4 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.100 (2.54) BSC 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) 0.070 (1.78) 0.060 (1.52) 0.045 (1.14) 0.280 (7.11) 0.250 (6.35) 0.240 (6.10) 0.060 (1.52) MAX 0.015 (0.38) MIN SEATING PLANE 0.015 (0.38) GAUGE PLANE 0.005 (0.13) MIN 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.430 (10.92) MAX 0.195 (4.95) 0.130 (3.30) 0.115 (2.92) 0.014 (0.36) 0.010 (0.25) 0.008 (0.20) COMPLIANT TO JEDEC STANDARDS MS-001 CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. CORNER LEADS MAY BE CONFIGURED AS WHOLE OR HALF LEADS. Figure 12. 8-Lead Plastic Dual In-Line Package [PDIP] (N-8) Dimensions shown in inches and (millimeters) 5.00 (0.1968) 4.80 (0.1890) 8 4.00 (0.1574) 3.80 (0.1497) 1 5 6.20 (0.2441) 4 5.80 (0.2284) 0.25 (0.0098) 0.10 (0.0040) 1.27 (0.0500) BSC 1.75 (0.0688) 1.35 (0.0532) COPLANARITY 0.10 SEATING PLANE 0.51 (0.0201) 0.31 (0.0122) 0.50 (0.0196) 45° 0.25 (0.0099) 8° 0° 1.27 (0.0500) 0.25 (0.0098) 0.40 (0.0157) 0.17 (0.0067) COMPLIANT TO JEDEC STANDARDS MS-012-AA 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 13. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) 012407-A 070606-A –14– REV. D ORDERING GUIDE Model1 AD818AN AD818ANZ AD818AR AD818ARZ AD818AR-REEL AD818ARZ-REEL AD818AR-REEL7 AD818ARZ-REEL7 AD818AR-EBZ 1 Z = RoHS Compliant Part. 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 −40°C to +85°C −40°C to +85°C −40°C to +85°C Package Description 8-Lead Plastic PDIP 8-Lead Plastic PDIP 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N, 13’’ Tape and Reel 8-Lead SOIC_N, 13’’ Tape and Reel 8-Lead SOIC_N, 7’’ Tape and Reel 8-Lead SOIC_N, 7’’ Tape and Reel Evaluation Board for 8-lead SOIC_N REVISION HISTORY 10/10—Rev. C to Rev. D Updated Outline Dimensions ....................................................... 14 Changes to Ordering Guide .......................................................... 15 5/03—Rev. B to Rev. C Renumbered Figures and TPCs........................................Universal Changes to Specifications ................................................................ 2 Changes to Ordering Guide ............................................................ 4 Changes to Figures 9 and 10 ......................................................... 12 Updated Outline Dimensions ....................................................... 14 AD818 Package Option N-8 N-8 R-8 R-8 R-8 R-8 R-8 R-8 ©2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D00872-0-10/10(D) REV. D –15–

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