OPA603AP

® OPA 603 OPA603 OPA 603 High Speed, Current-Feedback, High Voltage OPERATIONAL AMPLIFIER FEATURES q WIDE SUPPLY RANGE: ±4.5 to ±18V q BANDWIDTH: 100MHz, G = 1 to 10 q SLEW RATE: 1000V/µs q FAST SETTLING TIME: 50ns to 0.1% q HIGH OUTPUT CURRENT: ±150mA peak q HIGH OUTPUT VOLTAGE: ±12V APPLICATIONS q VIDEO AMPLIFIER q PULSE AMPLIFIER q SONAR, ULTRASOUND BUFFERS q ATE PIN DRIVERS q xDSL LINE DRIVER q FAST DATA ACQUISTION q WAVEFORM GENERATORS DESCRIPTION The OPA603 is a high-speed current-feedback op amp with guaranteed specifications at both ±5V and ±15V power supplies. It can deliver full ±10V signals into 150Ω loads with up to 1000V/µs slew rate. This allows it to drive terminated 75Ω cables. With 150mA peak output current capability it is suitable for driving load capacitance or long lines at high speed. In contrast with conventional op amps, the currentfeedback approach provides nearly constant bandwidth and settling time over a wide range of closedloop voltage gains. The OPA603 is available in a plastic 8-pin DIP and SO-16 surface-mount packages, specified over the industrial temperature range. +VS 7 +In 3 –In 2 VO 6 –VS 4 International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111 Internet: http://www.burr-brown.com/ • FAXLine: (800) 548-6133 (US/Canada Only) • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132 © 1989 Burr-Brown Corporation PDS-1026E Printed in U.S.A. February, 1995 SPECIFICATIONS: VS = ±15V ELECTRICAL At TA = +25°C, and RL = 150Ω, unless otherwise noted. OPA603AP, AU PARAMETER INPUT OFFSET VOLTAGE Initial vs Temperature vs Common-Mode Voltage vs Supply (tracking) Voltage vs Supply (non-tracking)(1) +INPUT BIAS CURRENT Initial vs Temperature vs Common-Mode vs Supply (tracking) vs Supply (non-tracking)(1) –INPUT BIAS CURRENT Initial vs Temperature vs Common-Mode vs Supply (tracking) vs Supply (non-tracking)(1) INPUT IMPEDANCE +Input –Input OPEN LOOP CHARACTERISTICS Transresistance Transcapacitance OUTPUT CHARACTERISTICS Voltage Peak Current Short-Circuit Current(2) Output Resistance, Open-Loop FREQUENCY RESPONSE Small-Signal Bandwidth(3) Gain Flatness, ±0.5dB Full-Power Bandwidth Differential Gain Differential Phase TIME DOMAIN RESPONSE Propagation Delay Rise and Fall Time Settling Time to 0.10% Slew Rate DISTORTION 2nd Harmonic Distortion 3rd Harmonic Distortion POWER SUPPLY Specified Operating Voltage Operating Voltage Range Current TEMPERATURE RANGE Specification Storage THERMAL RESISTANCE, θJA Soldered to Printed Circuit VO = ±10V 300 CONDITIONS MIN TYP MAX 5 VCM = ±10V VS = ±12V to ±18V |VS| = 12V to 18V 50 80 55 8 60 85 60 5 VCM = ±10V VS = ±12V to ±18V |VS| = 12V to 18V 30 200 50 150 500 100 300 25 VCM = ±10V VS = ±12V to ±18V |VS| = 12V to 18V 300 200 300 1500 5 || 2 30 || 2 440 1.8 ±12 150 250 70 160 75 10 0.03 0.025 10 10 50 1000 –60 –70 –65 –90 ±15 ±21 600 500 2000 UNITS mV µV/°C dB dB dB µA nA/°C nA/V nA/V nA/V µA nA/°C nA/V nA/V nA/V MΩ || pF Ω || pF kΩ pF V mA mA Ω MHz MHz MHz % Degrees ns ns ns V/µs dBc dBc V V mA °C °C °C/W RL = 150Ω VO = 0V G = +2 ±10 70 35 VO = 20Vp-p f = 4.43MHz, VO = 1V f = 4.43MHz, VO = 1V G = +2 10V Step G = +2, RL = 100Ω, f = 10MHz VO = 0.2Vp-p VO = 0.2Vp-p ±4.5 ±18 ±25 +85 +150 –25 –40 90 NOTES: (1) One power supply fixed at 15V; the other supply varied from 12V to 18V. (2) Observe power derating curve. (3) See bandwidth versus gain curve, Figure 5. The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems. ® OPA603 2 SPECIFICATIONS: VS = ±5V ELECTRICAL At TA = +25°C, and RL= 75Ω, unless otherwise noted. OPA603AP, AU PARAMETER INPUT OFFSET VOLTAGE Initial vs Temperature vs Common-Mode vs Supply (tracking) vs Supply (non-tracking)(1) +INPUT BIAS CURRENT Initial vs Temperature vs Common-Mode vs Supply (tracking) vs Supply (non-tracking)(1) –INPUT BIAS CURRENT Initial vs Temperature vs Common-Mode vs Supply (tracking) vs Supply (non-tracking)(1) INPUT IMPEDANCE +Input –Input OPEN LOOP CHARACTERISTICS Transresistance Transcapacitance OUTPUT CHARACTERISTICS Voltage Peak Current Short-Circuit Current(2) Output Resistance, Open-Loop FREQUENCY RESPONSE Small-Signal Bandwidth(3) Gain Flatness, ±0.5dB Full-Power Bandwidth Differential Gain Differential Phase TIME DOMAIN RESPONSE Propagation Delay Rise and Fall Time Settling Time to 0.10% Slew Rate DISTORTION 2nd Harmonic Distortion 3rd Harmonic Distortion POWER SUPPLY Specified Operating Voltage Operating Voltage Range Current TEMPERATURE RANGE Specification Storage THERMAL RESISTANCE, θJUNCTION-AMBIENT Soldered to Printed Circuit VO = ±2V 225 CONDITIONS MIN TYP MAX 6 VCM = ±3V VS = ±4V to ±6V |VS| = 4V to 6V 50 75 55 8 55 80 60 5 VCM = ±3V VS = ±4V to ±6V |VS| = 4V to 6V 30 350 100 200 600 200 300 25 VCM = ±3V VS = ±4V to ±6V |VS| = 4V to 6V 300 300 500 2500 3.3 || 2 30 || 2 330 2.4 ±2.75 150 250 80 140 65 20 0.03 0.025 15 20 60 750 G = +2, RL = 100Ω, f = 10MHz VO = 0.2Vp-p VO = 0.2Vp-p –67 –78 ±5 ±21 600 700 3000 UNITS mV µV/°C dB dB dB µA nA/°C nA/V nA/V nA/V µA nA/°C nA/V nA/V nA/V MΩ || pF Ω || pF kΩ pF V mA mA Ω MHz MHz MHz % Degrees ns ns ns V/µs dBc dBc V V mA °C °C °C/W RL = 75Ω VO = 0V G = +2 ±2 f = 4.43MHz, VO = 1V, RL = 150Ω f = 4.43MHz, VO = 1V, RL = 150Ω G = +2, RL = 100Ω ±4.5 ±18 ±25 +85 +150 –25 –40 90 NOTES: (1) One power supply fixed at 5V; the other supply varied from 4V to 6V. (2) Observe power derating curve. (3) See bandwidth versus gain curves, Figure 5. ® 3 OPA603 PIN CONFIGURATION Top View DIP PIN CONFIGURATION Top View NC NC 1 2 3 4 5 6 7 8 16 NC 15 NC 14 +VS 13 NC 12 VO 11 NC 10 NC 9 NC SO-16 NC –In +In –VS 1 2 3 4 8 7 6 5 NC +VS VO NC –In NC +In NC –VS NC NC: No Internal Connection. Solder to ground plane for improved heat dissipation. NC: No Internal Connection. Solder to ground plane for improved heat dissipation. ABSOLUTE MAXIMUM RATINGS Supply Voltage ................................................................................... ±18V Input Voltage Range ............................................................................ ±VS Differential Input Voltage ..................................................................... ±6V Power Dissipation ........................................................ See derating curve Operating Temperature ................................................................. +100°C Storage Temperature ..................................................................... +150°C Junction Temperature .................................................................... +150°C Lead Temperature (soldering, 10s) ............................................... +300°C (soldering SO-16 package, 3s) ...................... +260°C ELECTROSTATIC DISCHARGE SENSITIVITY This integrated circuit can be damaged by ESD. Burr-Brown recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. PACKAGE/ORDERING INFORMATION PACKAGE DRAWING NUMBER(1) 006 211 SPECIFIED TEMPERATURE RANGE –25°C to +85°C –25°C to +85°C PRODUCT OPA603AP OPA603AU PACKAGE Plastic DIP SO-16 NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book. ® OPA603 4 TYPICAL PERFORMANCE CURVES At TA = +25°C, unless otherwise noted. OUTPUT SWING vs TEMPERATURE 14 VS = ±15V Output Swing (V) OUTPUT SWING vs TEMPERATURE 3.1 RL = ∞ 13 Output Swing (V) RL = ∞ Positive Swing Positive Swing 2.9 RL = 75Ω 2.7 12 RL = 150Ω Negative Swing 2.5 VS = ±5V Negative Swing 11 2.3 10 –25 0 +25 +50 +75 +100 Temperature (°C) 2.1 –25 0 +25 +50 +75 +100 Temperature (°C) NONINVERTING INPUT BIAS CURRENT vs TEMPERATURE +5 +4 +3 +2 VS = ±15V +20 +10 +30 INVERTING INPUT BIAS CURRENT vs TEMPERATURE 0 –1 –2 –3 –4 –5 –25 0 +25 +50 +75 +100 Temperature (°C) VS = ±5V IB – (µA) I B + (µA) +1 0 –10 –20 –30 –25 0 +25 VS = ±15V VS = ±5V +50 +75 +100 Temperature (°C) COMMON-MODE REJECTION vs FREQUENCY 65 Common-Mode Rejection (dB) IB – Common-Mode Rejection Ratio (A/V) 10 –8 IB – COMMON-MODE REJECTION RATIO VS = ±15V VS = ±5V 55 10 –7 VS = ±15V 10 –6 VS = ±5V 45 10 –5 35 10 100 1k 10k 100k 1M 10M 10 –4 10 100 1k 10k 100k 1M 10M Frequency (Hz) Frequency (Hz) ® 5 OPA603 TYPICAL PERFORMANCE CURVES (CONT) At TA = +25°C, unless otherwise noted. POWER SUPPLY REJECTION vs FREQUENCY 90 Power Supply Rejection (dB) 85 POWER SUPPLY REJECTION vs FREQUENCY Power Supply Rejection (dB) Tracking Supplies 80 VS = ±15V Tracking Supplies 75 VS = ±5V 70 +VS 60 –VS 50 65 +VS –VS 55 45 40 10 100 1k 10k 100k 1M Frequency (Hz) 35 10 100 1k 10k 100k 1M Frequency (Hz) IB – Power Supply Rejection Ratio (A/V) Tracking Supplies 10 –6 IB – Power Supply Rejection Ratio (A/V) 10 –7 IB – PSRR vs FREQUENCY 10 –7 IB – PSRR vs FREQUENCY Tracking Supplies –VS +VS V S = ±15V 10 –6 –VS V S = ±5V 10 –5 10 –5 +VS 10 –4 10 –4 10 –3 10 10 100 1k 10k 100k 1M Frequency (Hz) –3 10 100 1k 10k 100k 1M Frequency (Hz) LARGE-SIGNAL HARMONIC DISTORTION vs FREQUENCY –30 Harmonic Distortion (dBc) Harmonic Distortion (dBc) LARGE-SIGNAL HARMONIC DISTORTION vs FREQUENCY –30 G = +2V/V V O = 2Vp-p RL = 100Ω –40 –50 –60 G = +2 V O = 2Vp-p RL = 100 Ω –40 –50 –60 –70 –80 2f 2f 3f –70 –80 VS = ±15V –90 –100 1 10 Frequency (MHz) 100 3f VS = ±5V –90 –100 1 10 Frequency (MHz) 100 ® OPA603 6 TYPICAL PERFORMANCE CURVES (CONT) At TA = +25°C, unless otherwise noted. SMALL-SIGNAL HARMONIC DISTORTION vs FREQUENCY –30 –30 G = +2V/V V O = 0.5Vp-p RL = 100Ω 2f VS = ±15V SMALL-SIGNAL HARMONIC DISTORTION vs FREQUENCY G = +2V/V V O = 0.5Vp-p RL = 100Ω 2f VS = ±5V Harmonic Distortion (dBc) –40 –50 –60 –70 –80 –90 –100 1 Harmonic Distortion (dBc) –40 –50 –60 –70 3f –80 –90 –100 1 10 Frequency (MHz) 100 3f 10 Frequency (MHz) 100 2-TONE, 3rd ORDER INTERMODULATION INTERCEPT 40 2.0 MAXIMUM POWER DISSIPATION vs TEMPERATURE Intercept Point (+dBm) 30 Power Dissipation (W) 1.5 Safe 1.0 VS = ±15V 20 VS = ±5V 0.5 10 10 20 30 Frequency (MHz) 40 50 –25 0 +25 +50 +75 +100 Temperature (°C) OPEN-LOOP TRANSIMPEDANCE vs TEMPERATURE 500 V S = ±15V 125 OPEN-LOOP OUTPUT RESISTANCE vs TEMPERATURE Open-Loop Output Resistance (Ω ) Open-Loop Transimpedance (kΩ ) 100 V S = ±5V 75 V S = ±15V 50 400 300 VS = ±5V 200 –25 0 +25 +50 +75 +100 Temperature (°C) 25 –25 0 +25 +50 +75 +100 Temperature (°C) ® 7 OPA603 TYPICAL PERFORMANCE CURVES (CONT) At TA = +25°C, unless otherwise noted. 10 3 INPUT NOISE vs FREQUENCY 10 VS = ±15V 3 10 3 INPUT NOISE vs FREQUENCY 10 VS = ±5V 3 Noise Voltage (nV/ Hz) Noise Voltage (nV/ Hz) 10 2 10 Inverting Current 2 Noise Current (pA/ Hz) 10 2 10 Inverting Current 2 10 Voltage 10 10 Voltage Voltage 10 Noninverting Current 1 1 10 100 1k 10k Frequency (Hz) 1 100k 1 1 Noninverting Current Noninverting Current 10 100 1k 10k 1 100k Frequency (Hz) LARGE-SIGNAL OUTPUT vs FREQUENCY 25 VS = ±15V Output Voltage (Vp-p) Output Voltage (Vp-p) LARGE-SIGNAL OUTPUT vs FREQUENCY 5 VS = ±5V 4 20 15 R L = 150 Ω 10 3 R L = 75Ω 2 5 1 0 100 1k 10k 100k Frequency (Hz) 1M 10M 100M 0 100 1k 10k 100k Frequency (Hz) 1M 10M 100M 10 6 OPEN-LOOP TRANSIMPEDANCE vs FREQUENCY 0 OPEN-LOOP PHASE vs FREQUENCY 10 VS = ±15V Phase Shift (Degrees) Transimpedance (Ω ) 5 VS = ±5V VS = ±5V VS = ±15V –45 10 4 –90 10 3 –135 10 2 –180 100 1k 10k 100k 1M 10M 100M 1G 100 1k 10k 100k 1M 10M 100M 1G Frequency (Hz) Frequency (Hz) ® OPA603 8 Noise Current (pA/ Hz) TYPICAL PERFORMANCE CURVES (CONT) At TA = +25°C, unless otherwise noted. Open- Loop Output Z Magnitude (Ω ) 80 OPEN-LOOP OUTPUT IMPEDANCE 90 Open- Loop Output Z Magnitude (Ω ) Open-Loop Output Z Phase (°) 80 OPEN-LOOP OUTPUT IMPEDANCE 90 Open-Loop Output Z Phase (°) ® 60 V S = ±15V 45 60 V S = ±5V 45 40 0 40 0 20 –45 20 –45 0 10k 100k 1M Frequency (Hz) 10M –90 100M 0 10k 100k 1M Frequency (Hz) 10M –90 100M 0.05% ∆ Gain 0.0625° ∆θ 200 IRE Full Scale Measured with Rohde & Schwarz Differential Gain/Phase Meter. Rohde & Schwarz SPF2 Video Signal Generator VS = ±5V 75Ω Rohde & Schwarz PVF Differential Gain/Phase Meter Scope Plotter 75Ω 499Ω 5pF 499Ω FIGURE 1. Video Differential Gain/Phase Performance. 9 OPA603 LARGE SIGNAL PULSE RESPONSE SMALL-SIGNAL FREQUENCY RESPONSE +6 2.5k Ω 2.5k VIN VIN 2.5kΩ 2.5k 100pF Input – VO + 150 150Ω Ω CL VO +3 Gain (dB) 50pF 0 VS = ±15V –3 NOTE: Feedback resistor value selected for reduced peaking. 1M Frequency (Hz) 10M 100M 0pF CL = 20pF 10pF Output –6 100k FIGURE 2. Dynamic Response, Inverting Unity-Gain. LARGE SIGNAL PULSE RESPONSE Input SMALL-SIGNAL FREQUENCY RESPONSE VVIN IN +26 + VO – 150Ω 150Ω CL VO 100pF +23 Gain (dB) 402Ω 402Ω 3570Ω 3570Ω +20 V S = ±15V +17 NOTE: Feedback resistor value selected for reduced peaking. 1M Frequency (Hz) 0pF CL = 20pF 10pF 50pF Output +14 100k 10M 100M FIGURE 3. Dynamic Response, Gain = +10. APPLICATIONS INFORMATION For most circuit configurations, the OPA603 current-feedback op amp can be treated like a conventional op amp. As with a conventional op amp, the feedback network connected to the inverting input controls the closed-loop gain. But with a current-feedback op amp, the impedance of the feedback network also controls the open-loop gain and frequency response. Feedback resistor values can be selected to provide a nearly constant closed-loop bandwidth over a very wide range of gain. This is in contrast to a conventional op amp where circuit bandwidth is inversely proportional to the closedloop gain, sharply limiting bandwidth at high gain. Figures 4a and 4b show appropriate feedback resistor values versus closed-loop gain for maximum bandwidth with minimal peaking. The dual vertical axes of these curves also show the resulting bandwidth. Note that the bandwidth remains nearly constant as gain is increased. With control of the open-loop characteristics of the op amp, dynamic behavior can be tailored to an application’s requirements. Lower feedback resistance gives wider bandwidth, more frequency-response peaking and more pulse response overshoot. The higher open-loop gain resulting from lower feedback network resistors also yields lower distortion. Higher feedback network resistance gives an over-damped response with little or no peaking and overshoot. This may be beneficial when driving capacitive loads. Feedback network impedance can also be varied to optimize dynamic performance. To achieve wider bandwidth, use a feedback resistor value somewhat lower than indicated in Figure 4. EXTENDING BANDWIDTH For gains less than approximately 20, bandwidth can be extended by adding a capacitor, CF, in parallel with a lower value for RF. The optimum feedback resistor value in this case is far lower than those shown in Figure 1. For ±15V operation, select RF with the following equation: ® OPA603 10 RF (Ω) = 30 • (30 – G) for VS = ±15V For example, for a gain of 10, use RF = 600Ω. Optimum values differ slightly for ±5V operation: RF (Ω) = 30 • (23 – G) for VS = ±5V CF will range from 1pF to 10pF depending on the selected gain, load, and circuit layout. Adjust CF to optimize bandwidth and minimize peaking. Figure 5 shows bandwidth which can be acheived using this technique. Typical values for this capacitor range from 1pF to 10pF depending on closed-loop gain and load characteristics. Too large a value of CF can cause instability. BANDWIDTH AND FEEDBACK RESISTOR vs INVERTING GAIN 60 3k 30 20 Voltage Gain (dB) VOLTAGE GAIN vs FREQUENCY G = 20, RF = 220 Ω, C F ≈ 8pF G = 10, RF = 560 Ω, C F ≈ 3pF 10 0 –10 G = 2, RF = 820 Ω, CF ≈ 3pF CF RF RI G=1+ RF RI 1G –20 1M 10M 100M Frequency (Hz) FIGURE 5. Bandwidth Results with Added Capacitor CF. Feedback Resistor (Ω) Closed-Loop Bandwidth (MHz) 52.5 2.25k CIRCUIT LAYOUT With any high-speed, wide-bandwidth circuitry, careful circuit layout will ensure best performance. Make short, direct circuit interconnections and avoid stray wiring capacitance— especially at the inverting input pin. A component-side ground plane will help ensure low ground impedance. Do not place the ground plane under or near the inputs and feedback network. Power supplies should be bypassed with good high-frequency capacitors positioned close to the op amp pins. In most cases, a 0.01µF ceramic capacitor in parallel with a 2.2µF solid tantalum capacitor at each power supply pin is adequate. The OPA603 can deliver high load current—up to 150mA peak. Applications with low impedance or capacitive loads demand large current transients from the power supplies. It is the power supply bypass capacitors which must supply these current transients. Larger bypass capacitors such as 10µF solid tantalum capacitors may improve performance in these applications. POWER DISSIPATION High output current causes increased internal power dissipation in the OPA603. Copper leadframe construction maximizes heat dissipation compared to conventional plastic packages. To achieve best heat dissipation, solder the device directly to the circuit board and use wide circuit board traces. Solder the unused pins, (1, 5 and 8) to a top-side ground plane for improved power dissipation. Limit the load and signal conditions depending on maximum ambient temperature to assure operation within the power derating curve. The OPA603 may be operated at reduced power supply voltage to minimize power dissipation. Detailed specifications are provided for both ±15V and ±5V operation. 45 RI 37.5 RF – + 1.5k 750 G= –RF RI 0 –100 30 –1 –10 Voltage Gain (V/V) (4a) BANDWIDTH AND FEEDBACK RESISTOR vs NONINVERTING GAIN 60 4k Closed-Loop Bandwidth (MHz) 52.5 3k 45 RF – 2k 37.5 + 1k G=1+ RF RI 0 100 RI 30 1 10 Voltage Gain (V/V) (4b) FIGURE 4. Feedback Resistor Selection Curves. UNITY-GAIN OPERATION As Figure 4b indicates, the OPA603 can be operated in unity gain. A feedback resistor (approximately 2.8kΩ) sets the appropriate open-loop characteristics and resistor RI is omitted. Just as with gains greater than one, the value of the feedback resistor (and capacitor if used) can be optimized for the desired dynamic response and load characteristics. Care should be exercised not to exceed the maximum differential input voltage rating of ±6V. Large input voltage steps which exceed the device’s slew rate of 1000V/µs can apply excessive differential input voltage. Feedback Resistor (Ω) ® 11 OPA603 APPLICATIONS CIRCUITS VIN +15V OPA603 100kΩ RF RG –15V 2-pole Butterworth HP f –3dB = 1MHz 1 f–3dB = 2π RC VIN C 100pF C 100pF 1590Ω R R 1590Ω VO OPA603 5pF VO 10kΩ 511Ω 866Ω G = 1.6 FIGURE 6. Offset Voltage Adjustment. FIGURE 9. High-Pass Filter — 1MHz. R G = 10 VIN OPA603 VO VIN R 110Ω C 100pF C 100pF 220Ω 2R 110Ω OPA603 5pF VO 1kΩ 1kΩ 110Ω 511Ω 261Ω (a) Varying inverting input Z changes dynamic response. 1kΩ 100Ω VIN 1MΩ VB : 0V - Max Bandwidth –V - Reduced Bandwidth (b) MFE2000 OPA603 G = –10 VO 1/2f C fC 2f C 22dB fC = G = 70 f C = 10MHz 1 2 2 π RC FIGURE 10. Bandpass Filter — 10MHz. R2 FIGURE 7. Controlling Dynamic Performance. A1 C 100pF VIN R 159Ω R 159Ω C 100pF OPA603 5pF VO VI OPA603 VO R L ≥ 150Ω for ±10V Out R1 R3 (1) R4 2-pole Butterworth LP f –3dB = 10MHz 1 f –3dB = 2π RC 511Ω 866Ω G = 1.6 This composite amplifier uses the OPA603 current-feedback op amp to provide extended bandwidth and slew rate at high closed-loop gain. The feedback loop is closed around the composite amp, preserving the precision input characteristics of the OPA627/637. Use separate power supply bypass capacitors for each op amp. See Application Bulletin AB-007 for details. NOTE: (1) Minimize capacitance at this node. SLEW RATE (V/µs) 700 500 FIGURE 8. Low-Pass Filter — 10MHz. GAIN (V/V) 100 1000 A1 OP AMP OPA627 OPA637 R1 (Ω) 50.5(1) 49.9 R2 (kΩ) 4.99 4.99 R3 (Ω) 20 12 R4 (kΩ) 1 1 –3dB (MHz) 15 11 NOTE: (1) Closest 1/2% value. FIGURE 11. Precision-Input Composite Amplifier. ® OPA603 12