ad797bn Analog Devices, Inc., ad797bn Datasheet
ad797bn
Related parts for ad797bn
ad797bn Summary of contents
Page 1
... DECOMPENSATION AND DISTORTION 1 8 AD797 NEUTRALIZATION – +IN OUTPUT 3 6 –V OFFSET NULL TOP VIEW MEASUREMENT LIMIT 300 1k 3k 10k 30k 100k FREQUENCY (Hz) Figure 3. THD vs. Frequency www.analog.com © 2005 Analog Devices, Inc. All rights reserved. 0.001 0.0003 0.0001 300k ...
Page 2
AD797 TABLE OF CONTENTS Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Typical Performance Characteristics ............................................. 6 Theory of Operation ...................................................................... 11 Noise and Source Impedance Considerations........................ 12 Low Frequency Noise................................................................. 12 Wideband Noise ......................................................................... 13 REVISION HISTORY 7/05—Rev. ...
Page 3
SPECIFICATIONS @ T = +25°C and V = ±15 V dc, unless otherwise noted Table 1. Parameter INPUT OFFSET VOLTAGE Offset Voltage Drift INPUT BIAS CURRENT INPUT OFFSET CURRENT OPEN-LOOP GAIN DYNAMIC PERFORMANCE Gain Bandwidth Product –3 dB ...
Page 4
AD797 Parameter OUTPUT RESISTANCE POWER SUPPLY Operating Range Quiescent Current 1 Full Power Bandwidth = Slew Rate/2 π PEAK 2 Specified using external decompensation capacitor; see Applications section. 3 Output current for |V – > 4 ...
Page 5
ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage 1 Internal Power Dissipation @ 25°C Input Voltage 2 Differential Input Voltage Output Short-Circuit Duration Storage Temperature Range (Cerdip) Storage Temperature Range (N, R Suffix) Operating Temperature Range AD797A/B Lead Temperature Range ...
Page 6
AD797 TYPICAL PERFORMANCE CHARACTERISTICS SUPPLY VOLTAGE (±V) Figure 4. Common-Mode Voltage Range vs. Supply OUT –V OUT SUPPLY VOLTAGE (±V) Figure 5. Output ...
Page 7
SUPPLY VOLTAGE (±V) Figure 10. Quiescent Supply Current vs. Supply Voltage FREQ = 1kHz R = 600Ω + ±5 ...
Page 8
AD797 100 1k 10k FREQUENCY (Hz) Figure 16. Input Voltage Noise Spectral Density 120 PHASE MARGIN 100 WITH GAIN 40 *RS = 100 20 WITH R 0 100 1k 10k ...
Page 9
S ** 1kΩ AD797 –V S Figure 22. Inverter Connection **See Figure 35 1μs 100 Figure 23. Inverter Large Signal Pulse Response 50mV 100ns 100 ...
Page 10
AD797 50mV 100 Figure 28. 16-Bit Settling Time Positive Input Pulse 500ns 100 Figure 29. 16-Bit Settling Time Negative Input Pulse Rev Page 50mV 500ns ...
Page 11
THEORY OF OPERATION The architecture of the AD797 was developed to overcome inherent limitations in previous amplifier designs. Previous precision amplifiers used three stages to ensure high open-loop gain ( Figure 30) at the expense of additional frequency compen- sation ...
Page 12
AD797 +IN –IN C CURRENT Q1 Q2 MIRROR Figure 32. AD797 Block Diagram NOISE AND SOURCE IMPEDANCE CONSIDERATIONS The AD797’s ultralow voltage noise of 0.9 nV/√Hz is achieved with special input ...
Page 13
S ** 1Ω 1.5μF AD797 6 V OUT –V S Figure 34. Test Setup for Measuring 0 Noise **Use Power Supply Bypassing Shown in Figure 35 WIDEBAND NOISE Due ...
Page 14
AD797 C L 100Ω AD797 –V S *SEE TEXT Figure 37. Alternative Voltage Follower Connection **Use Power Supply Bypassing Shown ...
Page 15
DRIVING CAPACITIVE LOADS The capacitive load driving capabilities of the AD797 are displayed in Figure 41. At gains over 10, usually no special precautions are necessary. If more drive is desirable the circuit in Figure 42 should be used. Here ...
Page 16
AD797 The benefits of this begin at closed-loop gains of 100 and up. A maximum value of ≈ gains of 1000 and up is recommended gain of 1000, the bandwidth is 450 kHz. Table 6 and ...
Page 17
FREQUENCY (Hz) Figure 47. Output Voltage Noise Spectral Density for Differential Line Receiver –90 –100 –110 MEASUREMENT –120 OPTIONAL –130 100 300 1k 3k 10k FREQUENCY (Hz) Figure 48. Total ...
Page 18
AD797 Amorphous (Photodiode) Detector Large area photodiodes (C ≥ 500 pF) and certain image S detectors (amorphous Si) have optimum performance when used in conjunction with amplifiers with very low voltage rather than very low current noise. Figure 51 shows ...
Page 19
OUTLINE DIMENSIONS PIN 1 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR ...
Page 20
... AD797BRZ-REEL7 −40°C to +85° Pb-free part. ©2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Package Description 8-Lead Plastic Dual In-Line Package [PDIP] 8-Lead Plastic Dual In-Line Package [PDIP] 8-Lead Standard Small Outline Package [SOIC_N] ...