AD797 Analog Devices, AD797 Datasheet
AD797
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AD797 Summary of contents
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... ADCs or the outputs of high resolution DACs especially when used in critical applications such as seismic detection and spectrum analyzers. Key features such output current drive and the specified power supply voltage range of ± ±15 V make the AD797 an excellent general-purpose amplifier. –90 –100 – ...
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... 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 Rev. E Updated Figure 1 Caption ............................................................... 1 Deleted Metallization Photo ........................................................... 6 Changes to Equation 1 ................................................................... 12 Updated Outline Dimensions ....................................................... 19 Changes to Ordering Guide .......................................................... 20 10/02— ...
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... AD797 Unit μV μV μV/°C μA μ V/μV V/μV V/μV V/μV V/V MHz MHz MHz kHz V/μ p-p nV/√Hz nV/√ ...
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... V, A > 200 kΩ. S OUT OL 4 Differential input capacitance consists of 1.5 pF package capacitance and 18.5 pF from the input differential pair. Conditions V Min kHz V ±5 ±5 V, ±15 V Rev Page AD797A AD797B Typ Max Min Typ Max 3 3 ±18 ±5 ±18 8.2 10.5 8.2 10.5 Unit mΩ ...
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... JA 2 The AD797’s inputs are protected by back-to-back diodes. To achieve low noise, internal current limiting resistors are not incorporated into the design of this amplifier. If the differential input voltage exceeds ±0.7 V, the input current should be limited to less than series protection resistors. ...
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... AD797 TYPICAL PERFORMANCE CHARACTERISTICS SUPPLY VOLTAGE (±V) Figure 4. Common-Mode Voltage Range vs. Supply OUT –V OUT SUPPLY VOLTAGE (±V) Figure 5. Output Voltage Swing vs. Supply ± 15V ± 100 LOAD RESISTANCE (Ω) Figure 6 ...
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... CMR 10 100 1k 10k 100k FREQUENCY (Hz 600Ω +10 FREQ = 10kHz NOISE BW = 100kHz V = ± ± 0.1 1 OUTPUT LEVEL (V) ±15V SUPPLIES = 600 Ω ±5V SUPPLIES 100k 1M FREQUENCY (Hz) Figure 15. Large Signal Frequency Response AD797 150 125 100 10M ...
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... 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 100k FREQUENCY (Hz) Figure 17. Open-Loop Gain and Phase vs. Frequency *See Figure 25 300 OVER COMPENSATED 150 0 –150 UNDER COMPENSATED – ...
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... Figure 26. Follower Large Signal Pulse Response 100 Figure 27. Follower Small Signal Pulse Response Rev Page 100Ω AD797 V 6 OUT 600Ω –V S Figure 25. Follower Connection **See Figure 35 5V 1μs 50mV 100ns AD797 ...
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... 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 ...
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... Q10 subtraction. Therefore, the distortion cancellation does not OUT affect the stability or frequency response of the amplifier. With Q9 only 500 μA of output stage bias, the AD797 delivers a 1 kHz Q8 sine wave into 60 Ω rms with only 1 ppm of distortion. Q11 Rev ...
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... N where r = total input source resistance. S This equation is plotted for the AD797 in Figure 33. Because optimum dc performance is obtained with matched source resistances, this case is considered even though it is clear from Equation 1 that eliminating the balancing source resistance lowers the total noise by reducing the total r At very low source resistance (r < ...
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... Figure 34. Test Setup for Measuring 0 Noise **Use Power Supply Bypassing Shown in Figure 35 WIDEBAND NOISE Due to its single stage design, the noise of the AD797 is flat over frequencies from less than beyond 1 MHz. This is not true of most dc precision amplifiers where second stage noise contributes to input referred noise beyond the audio frequency range ...
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... The I-to-V converter is a special case of the follower configu- ration. When the AD797 is used in an I-to-V converter, for example as a DAC buffer, the circuit of used. The value of C depends on the DAC and again greater than 33 pF, a 100 Ω series resistor is required. ...
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... Figure 42. Recommended Circuit for Driving a High Capacitance Load **Use Power Supply Bypassing Shown in Figure 35 SETTLING TIME The AD797 is unique among ultralow noise amplifiers in that it settles to 16 bits (<150 μV) in less than 800 ns. Measuring this performance presents a challenge. A special test setup (Figure 43) was developed for this purpose. The input signal was obtained from a resonant reed switch pulse generator, available from Tektronix as calibration Fixture No ...
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... MRI imaging. It allows extraction of a low level signal in the presence of common-mode noise shown in Figure 47, the AD797 provides this function with only 9 nV/√Hz noise at the output. Figure 45 shows the AD797’s 20-bit THD performance over the audio band and 16-bit accuracy to 250 kHz ...
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... The circuit of Figure 49 combines the AD797 with the AD811 in just such an application. Using the component values shown, this circuit is capable of better than −90 dB THD with a ±5 V, 500 kHz output signal. The ...
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... Figure 52. Total Integrated Voltage Noise and V of Amorphous Detector Preamp Professional Audio Signal Processing—DAC Buffers The low noise and low distortion of the AD797 make it an ideal choice for professional audio signal processing. An ideal I-to-V converter for a current output DAC would simply be a resistor to ground, were it not for the fact that most DACs do not operate linearly with voltage on their output ...
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... COMPLIANT TO JEDEC STANDARDS MS-012-AA Figure 56. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) Rev Page 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.195 (4.95) 0.130 (3.30) 0.115 (2.92) 0.014 (0.36) 0.010 (0.25) 0.008 (0.20) 0.430 (10.92) MAX 0.50 (0.0196) × 45° 0.25 (0.0099) 8° 0° 1.27 (0.0500) 0.40 (0.0157) AD797 ...
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... AD797ARZ −40°C to +85°C 1 AD797ARZ-REEL −40°C to +85°C 1 AD797ARZ-REEL7 −40°C to +85°C AD797BR −40°C to +85°C AD797BR-REEL −40°C to +85°C AD797BR-REEL7 −40°C to +85°C 1 AD797BRZ −40°C to +85°C 1 AD797BRZ-REEL −40°C to +85°C 1 AD797BRZ-REEL7 − ...