AD8021 Analog Devices, AD8021 Datasheet
AD8021
Specifications of AD8021
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AD8021 Summary of contents
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... The AD8021 is stable over temperature with low input offset voltage drift and input bias current drift, 0.5 μV/°C and 10 nA/°C, respectively. The AD8021 is also capable of driving a 75 Ω line with ±3 V video signals. The AD8021 is both technically superior and priced considerably less than comparable amps drawing much higher quiescent current ...
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... Updated Format..................................................................Universal Applications..................................................................................... 19 Using the Disable Feature.......................................................... 20 Theory of Operation ...................................................................... 21 PCB Layout Considerations...................................................... 21 Driving 16-Bit ADCs ................................................................. 22 Differential Driver...................................................................... 22 Using the AD8021 in Active Filters ......................................... 23 Driving Capacitive Loads.......................................................... 23 Outline Dimensions ....................................................................... 25 Ordering Guide .......................................................................... 25 7/03—Rev Rev. C Deleted All References to Evaluation Board...................Universal Replaced Figure 2 ..............................................................................5 Updated Outline Dimensions....................................................... 20 2/03— ...
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... MHz 50% logic to 50% output 50% logic to 50% output O V − V DISABLE LOGIC REFERENCE LOGIC REFERENCE = 0.4 V DISABLE = 4.0 V Rev Page AD8021 AD8021AR/AD8021ARM Min Typ Max Unit 355 490 MHz 160 205 MHz 150 185 MHz 110 ...
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... V = ± Rev Page AD8021AR/AD8021ARM Min Typ Max 30 33 ±2.25 ±5 ±12.0 7.0 7.7 1.3 1.6 −86 −95 −86 −95 AD8021AR/AD8021ARM Min Typ Max 520 560 175 220 170 200 125 165 105 130 140 170 265 340 400 460 21 90 −95 − ...
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... Typ Max −10.2 to +9.8 −10.6 to +10.2 70 115 15/120 − 1.80/1. ±2.25 ±5 ±12.0 7.8 8.6 1.7 2.0 −86 −96 −86 −100 AD8021AR/AD8021ARM Min Typ Max 270 305 155 190 135 165 95 130 80 110 110 140 210 280 290 390 28 40 −84 −91 −68 −81 2 ...
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... O V − V DISABLE LOGIC REFERENCE LOGIC REFERENCE = 0.4 V DISABLE = 4.0 V LOGIC REFERENCE = 0.4 V DISABLE = 0.4 V Output enabled Output disabled −0 +0 Rev Page AD8021AR/AD8021ARM Min Typ Max Unit 0.4 1.0 mV 0.8 μV/°C 7.5 10.3 μA 10 nA/°C 0.1 0.5 ±μ MΩ ...
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... Operating Temperature Range Lead Temperature (Soldering, 10 sec) 1 The AD8021 inputs are protected by diodes. Current-limiting resistors are not used to preserve the low noise differential input exceeds ±0.8 V, the input current should be limited to ±10 mA. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only ...
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... Pin 1, the part is disabled. (See the Specifications tables for exact disable and enable voltage levels.) If the disable feature is not going to be used, Pin 8 can be tied logic high source, and Pin 1 can be tied to ground or logic low. Alternatively, if Pin 1 and Pin 8 are not connected, the part enabled state. S AD8021 LOGIC 1 8 ...
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... Figure 9. Small Signal Frequency Response vs. Frequency and Supply p-p, Inverting (See Figure 50) OUT 0.1V AND 50mV p-p OUT p-p OUT p-p OUT 1 0 –1 1M 10M 100M FREQUENCY (Hz) Figure 10. Frequency Response vs. Frequency and V (See Figure 48) AD8021 = 2 V p-p, OUT V = ± ±12V ± Noninverting OUT ...
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... AD8021 100Ω 0.1M 1M 10M FREQUENCY (Hz) Figure 11. Large Signal Frequency Response vs. Frequency and Load, Noninverting (See Figure 49 –40° +85° OUT 2V p-p 2 +25° –40°C –1 1M 10M FREQUENCY (Hz) Figure 12 ...
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... Figure 21. Third-Order Intercept vs. Frequency and Supply Voltage L –50 –60 –70 –80 –90 –100 R –110 –120 10M 20M 1 Figure 22. Second and Third Harmonic Distortion vs Rev Page AD8021 Δ 0.2MHz OUT 976Ω 53.6Ω 9.7 10.0 10.3 FREQUENCY (MHz ± ± ...
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... AD8021 –50 –60 SECOND – 5MHz C –80 THIRD –90 SECOND f = 1MHz –100 C –110 THIRD –120 p-p) OUT Figure 23. Second and Third Harmonic Distortion vs. V Fundamental Frequency (f –40 – 5MHz C –60 SECOND –70 THIRD –80 SECOND f = 1MHz –90 C THIRD –100 –110 ...
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... Figure 32. Large Signal Transient Response vs Noninverting OUT 0 200 250 p-p O +0.01% –0.01% 160 200 (See Figure 48) L Rev Page AD8021 p ± 120 160 TIME (ns) (See Figure 48 ±3V = 1V/DIV 1kΩ OUT ...
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... AD8021 100 PULSE WIDTH = 120ns 20 0 –20 PULSE WIDTH = 300µs –40 5V –60 0V – –100 TIME (µs) Figure 35. Long-Term Settling –10 –20 –30 –40 – TIME (ns) Figure 36. Small Signal Transient Response, V ...
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... Figure 45. Output Impedance vs. Frequency, Chip Disabled 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 400 500 10k (See Figure 53) Rev Page AD8021 1M 10M 100M FREQUENCY (Hz) 100k 1M 10M 100M FREQUENCY (Hz) (See Figure 55) –PSRR V = ±2.5V +PSRR ±5V ...
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... AD8021 8.5 8.0 7.5 7.0 6.5 6.0 5.5 –50 – TEMPERATURE (°C) Figure 47. Quiescent Supply Current vs. Temperature 50 75 100 Rev Page ...
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... S 49.9Ω AD8021 1 49.9Ω LOGIC REF DISABLE –V S 7pF 499Ω 499Ω Figure 54. Input-to-Output Isolation, Chip Disabled AD8021 100Ω 50Ω 7pF –V S Figure 55. Output Impedance, Chip Disabled AD8021 HP8753D NETWORK 976Ω 53.6Ω ...
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... AD8021 BIAS HP8753D BNC NETWORK ANALYZER 50Ω 49.9Ω 249Ω –V S 7pF 499Ω 499Ω Figure 56. Positive PSRR 50Ω 50Ω CABLE 976Ω 53.6Ω Rev Page BIAS HP8753D BNC NETWORK ANALYZER 50Ω 50Ω –V S 50Ω CABLE ...
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... To a first-order approximation, voltage feedback op amps have a fixed gain bandwidth product. For example, if its −3 dB bandwidth is 200 MHz for a gain + gain +10, its bandwidth is only about 20 MHz. The AD8021 is a voltage feedback op amp with a minimal C 1.5 pF. By adding an external compensation capacitor, C user can circumvent the fixed gain bandwidth limitation of other voltage feedback op amps ...
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... With the AD8021, a variety of trade-offs can be made to fine- tune its dynamic performance. Sometimes more bandwidth or slew rate is needed at a particular gain. Reducing the compensation capacitance, as illustrated in Figure 7, increases the bandwidth and peaking due to a decrease in phase margin. On the other hand, if more stability is needed, increasing the compensation capacitor decreases the bandwidth while increasing the phase margin ...
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... C connected. The output stage preserves this high impedance with a current gain of 5000, so that the AD8021 can maintain a high open-loop gain even when driving heavy loads. Two internal diode clamps across the inputs (Pin 2 and Pin 3) protect the input transistors from large voltages that could otherwise cause emitter-base breakdown, which would result in degradation of offset voltage and input bias current ...
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... Third Harmonic Distortion THD SFDR DIFFERENTIAL DRIVER The AD8021 is uniquely suited as a low noise differential driver for many ADCs, balanced lines, and other applications requiring differential drive. If pairs of internally compensated op amps are configured as inverter and follower, the noise gain of the inverter is higher than that of the follower section, resulting in an imbalance in the frequency response (see Figure 66) ...
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... Configured for a Gain of +2 and a Gain of −2, (Note the Close Gain Match) USING THE AD8021 IN ACTIVE FILTERS The low noise and high gain bandwidth of the AD8021 make it an excellent choice in active filter circuits. Most active filter literature provides resistor and capacitor values for various filters but neglects the effect of the op amp’ ...
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... AD8021 18 FET + OBE 16 R SNUB 5 49.9 Ω 14 49.9 Ω 33pF L 1k Ω 12 – 499 Ω 499 Ω 8pF SNUB 0.1 1.0 10 FREQUENCY (MHz) Figure 70. Peaking vs. R and C SNUB C = 7pF Ω R SNUB C = 8pF Ω R SNUB = 17.4 Ω 100 ...
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... AD8021ARZ-REEL7 −40°C to +85°C AD8021ARM −40°C to +85°C AD8021ARM-REEL −40°C to +85°C AD8021ARM-REEL7 −40°C to +85°C 1 AD8021ARMZ −40°C to +85°C 1 AD8021ARMZ-REEL −40°C to +85°C 1 AD8021ARMZ-REEL7 −40°C to +85° Pb-free part, # denotes lead-free product may be top or bottom marked. ...
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... AD8021 NOTES Rev Page ...
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... NOTES Rev Page AD8021 ...
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... AD8021 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01888-0-5/06(F) Rev Page ...