AD600 Analog Devices, Inc., AD600 Datasheet
AD600
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AD600 Summary of contents
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... Each independent channel provides a gain + the AD600 and − + the AD602. The lower gain of the AD602 results in an improved signal-to-noise ratio (SNR) at the output. ...
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... A 100 dB RMS/AGC System with Minimal Gain Error (Parallel Gain with Offset) ........................................................ 22 A 120 dB RMS/AGC System with Optimal SNR (Sequential Gain) ....................................................................... 23 Outline Dimensions ....................................................................... 27 Ordering Guide .......................................................................... 28 5/02—Rev Rev. C Changes to Specifications.................................................................2 Renumber Tables and TPCs...................................................Global 8/01—Rev Rev. B Changes to Accuracy Section of AD600A/AD602A column......2 Rev Page ...
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... SPECIFICATIONS Each amplifier section 25° Specifications for the AD600/AD602 are identical, unless otherwise noted. Table 1. Parameter INPUT CHARACTERISTICS Input Resistance Input Capacitance 2 Input Noise Spectral Density Noise Figure Common-Mode Rejection Ratio OUTPUT CHARACTERISTICS −3 dB Bandwidth Slew Rate 3 Peak Output ...
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... With an additional 1 kΩ pull-down resistor The dc gain of the main amplifier in the AD600 is × 113; therefore, an input offset of only 100 μV becomes an 11.3 mV output offset. In the AD602, the amplifier’s gain is × 35.7; therefore, an input offset of 100 μV becomes a 3.57 mV output offset. ...
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... S ±V S 600 mW 0°C to 70°C −40°C to +85°C −55°C to +125°C −65°C to +150°C 300°C 85°C/W 100°C/W 120°C/W Rev Page AD600/AD602 ...
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... CH1 Gain-Control Input HI (Positive Voltage Increases CH1 Gain) 1 C1HI C1LO 16 A1HI 2 A1CM A1LO A1OP 3 14 – GAT1 4 13 VPOS REF GAT2 5 12 VNEG A2LO 6 11 A2OP – A2HI A2CM + 8 9 C2LO C2HI AD600 / AD602 Figure 2. Pin Configuration Rev Page ...
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... Rev Page AD600/AD602 10.0 9.8 9.6 9.4 9.2 9.0 8.8 8.6 8.4 8.2 8.0 –0.7 –0.5 –0.3 –0.1 0.1 0.3 GAIN CONTROL VOLTAGE (V) Figure 6. AD600 and AD602 Typical Group Delay vs 10dB/DIV CENTER FREQ 1MHz 10kHz/DIV OUT –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 –2.2 –2.4 –2.6 –2.8 –3.0 –3.2 –3 ...
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... GAIN = 20dB 98 97 GAIN = 0dB 100k 1M FREQUENCY (Hz) Figure 9. Input Impedance vs. Frequency AD600 3 2 AD602 1 0 –1 –2 –3 –4 –0.7 –0.5 –0.3 –0.1 0.1 GAIN CONTROL VOLTAGE (V) Figure 10. Output Offset Voltage vs. Gain Control Voltage (Control Channel Feedthrough) 1V VOUT ...
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... Figure 18. CMRR vs. Frequency –10 AD600 –20 –30 –40 –50 –60 –70 –80 100k 1M Figure 19. PSRR vs. Frequency 10 AD600: CH1 G = 40dB CH2 G = 20dB, V AD602: CH1 G = 30dB, V –10 CH2 G = 0dB, V BOTH rms1, R OUT – 500Ω L CROSSTALK = 20log –30 –40 –50 – ...
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... This last calculation would be important if the AD600 were preceded, for example 900 Ω resistor to allow operation from inputs up to ±10 V rms. However, in most cases, the low impedance of the source limits the maximum noise resistance ...
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... V rms and the NSD at the output of the AD600 is fixed at 113 × 114 nV/√Hz, or 158 nV/√Hz. Therefore MHz bandwidth, the output SNR is 76 dB. The input NSD of the AD600/AD602 are the same, but because of the 10 dB lower gain in the AD602’ ...
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... A1CM) drives the input of A2 via a high-pass network (usually just a capacitor) that rejects the dc offset. The nominal gain range is now – +82 dB for the AD600 or − +62 dB for the AD602. There are several options in connecting the gain-control inputs. ...
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... A2 amplifiers can be made to cancel. Figure 31 shows the much lower gain ripple when configured in this manner. Figure 32 plots the SNR as a function of gain very similar to that in the parallel mode. –1.07dB 1.875 2 82.14 Rev Page AD600/AD602 ...
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... AD600/AD602 COMBINED –10 –0.5 0 0.5 1.0 1 Figure 27. Plot of Separate and Overall Gains in Sequential Control –1 –2 –3 –4 –5 –6 –7 –8 –0.5 0 0.5 1.0 1 Figure 28. Gain Error for Cascaded Stages—Sequential Control – ...
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... However always true of high accuracy, high speed analog circuits, the schematic is only part of the story; this is no less true for the AD600/ AD602. Appropriate choices in the overall board layout and the type and placement of power supply decoupling components are very important ...
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... Larger gain ranges can be accommodated by cascading amplifiers. Combinations built by cascading two amplifiers include − +60 dB (using one AD602), − +70 dB (using ½ AD602 followed by ½ AD600), and (using one AD600). In multiple-channel applications, extra protection against oscillation can be provided by using amplifier sections from different packages ...
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... Figure 37 provides an example of the ease with which the of Q1 increases. e AD600 can be connected as an AGC amplifier. A1 and A2 are cascaded, with attenuation introduced by the 100 Ω resistor R1, while a time constant formed by C1 and the 50 Ω of net resistance at the input of A2. This has the dual effect of lowering the overall gain range from − ...
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... Thus, an input rms would be required to produce rms output at the minimum gain, which exceeds the 1 V rms maximum input specification of the AD600. The available gain range is therefore ( X5000). Since the gain scaling is 15.625 mV/dB (because of the cascaded stages), the ...
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... V) or restrict the dynamic range of the signal to RF about 60 dB. OUTPUT As in the previous case, the two amplifiers of the AD600 are used in cascade. However, the 6 dB attenuator and low-pass filter found in Figure 21 are replaced by a unity gain buffer amplifier U3A, whose 4 MHz bandwidth eliminates the risk of instability at the highest gains ...
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... Any difference in these voltages is integrated by the op amp U3B, with a time constant formed by the parallel sum of R6/R7 and C3. Now, if the output of the AD600 is too high, V rms is greater than the setpoint of 316 mV, causing the output of U3B—that is, V —to ramp up (note that the integrator is OUT noninverting) ...
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... ACCURACY dB OUTPUTS The next two applications double as both AGC amplifiers and measurement systems. In both, precise gain offsets are used to achieve either a high gain linearity of ±0.1 dB over the full 100 dB range or the optimal SNR at any gain. Rev Page AD600/AD602 C1HI 16 A1CM 15 A1OP 14 – ...
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... A1OP 3 14 – GAT1 VPOS 4 13 REF GAT2 VNEG 5 12 A2LO 6 11 A2OP – A2 A2CM A2HI 7 10 1/4 + C2LO C2HI AD600 C5 22µF +5V DEC 1 VINP VPOS AD636 R11 46.4kΩ VNEG CAVG NC R10 4.7µF 3.16kΩ 10 VLOG COMM ...
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... Hz are provided by R1/C1 and R4/C2; op amp sections U3A and U3B (AD713) are used to provide impedance buffering, because the input resistance of the AD600 is only 100 Ω. A further provided by C4 and the 6.7 kΩ input resistance of the AD636 rms converter. ...
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... GAT1 VPOS 4 13 REF GAT2 VNEG 5 12 A2LO 6 A2OP 11 – U3B A2 A2CM A2HI 7 10 1/4 + C2LO AD713 C2HI AD600 C5 22µF +6V DEC 1 VPOS 14 VINP AD636 R11 56.2kΩ VNEG CAVG R10 4.7µF 3.16kΩ VLOG COMM ...
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... SNR relative to OUT 0 dBV, which is almost the maximum output capability of the AD600. Results for the simultaneous mode can be seen in Figure 55. The SNR degrades uniformly as the gain is increased. Note that since the inverting gain control was used, the gain in this curve and in Figure 56 decreases for more positive values of the gain-control voltage ...
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... AGC amplifiers. The precise values of the AD600’s maximum and minimum gain (not 0 dB and +40 dB but −1.07 dB and +41.07 dB) explain the rather odd values of the offset values that are used. ...
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... COPLANARITY 0° 0.10 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 59. 16-Lead Standard Small Outline Package [SOIC_W] Rev Page AD600/AD602 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) ...
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... Z = Pb-free part. 2 Refer to AD600/AD602 military data sheet. Also available as 5962-9457201MEA. 3 Refer to AD600/AD602 military data sheet. Also available as 5962-9457202MEA. ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Temperature Range −40°C to +85°C − ...