AD7720BRU Analog Devices Inc, AD7720BRU Datasheet
AD7720BRU
Specifications of AD7720BRU
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AD7720BRU Summary of contents
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FEATURES 12.5 MHz Master Clock Frequency +2 1.25 V Input Range Single Bit Output Stream 90 dB Dynamic Range Power Supplies: AVDD, DVDD On-Chip 2.5 V Voltage Reference 28-Lead TSSOP GENERAL DESCRIPTION ...
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AD7720–SPECIFICATIONS Parameter STATIC PERFORMANCE Resolution Differential Nonlinearity Integral Nonlinearity Precalibration Offset Error 2 Precalibration Gain Error 3 Postcalibration Offset Error 2, 3 Postcalibration Gain Error Offset Error Drift Gain Error Drift Unipolar Mode Bipolar Mode ANALOG INPUTS Signal Input Span ...
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Parameter LOGIC INPUTS V , Input High Voltage Input Low Voltage Input Current INH C , Input Capacitance IN LOGIC OUTPUTS V , Output High Voltage Output Low Voltage OL POWER ...
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AD7720 TIMING CHARACTERISTICS Limit at T MIN Parameter (B Version) f 100 MCLK 0. MCLK t 0. MCLK ...
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... Transient currents 100 mA will not cause SCR latchup. Model AD7720BRU CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. ...
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AD7720 Pin No. Mnemonic 1 REF2 2, 14, 18, 20, 24, 26 AGND STBY 5 DVAL 6, 15 DGND BIP 9 MZERO 10 DATA 11 SCLK 12 RESETO 16 XTAL1/MCLK CMOS Logic Clock ...
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TERMINOLOGY (IDEAL FIR FILTER USED WITH AD7720 [FIGURE 1]) Integral Nonlinearity This is the maximum deviation of any code from a straight line passing through the endpoints of the transfer function. The endpoints of the transfer function are zero scale ...
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AD7720–Typical Characteristics (AVDD = DVDD = 5 +25 C; CLKIN = 12.5 MHz, AIN = 20 kHz, Bipolar Mode noted) 110 100 90 SFDR 80 S/ (N+ –40 –30 –20 –10 0 ...
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FREQUENCY – MHz Figure 15. Modulator Output ( MCLK/2) 0 CLKIN = 12.5MHz –20 SNR = 90.1dB –40 S/(N+D) = 89.2dB SFDR = ...
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AD7720 CIRCUIT DESCRIPTION Sigma-Delta ADC The AD7720 ADC employs a sigma-delta conversion technique that converts the analog input into a digital pulse train. The analog input is continuously sampled by a switched capacitor modulator at twice the rate of the ...
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C R 2.7nF 100 C 2.7nF R 100 C 2.7nF Figure 24. Differential Input with Antialiasing A capacitor between the two input pins sources or sinks charge to allow most of the charge that is needed by one input to ...
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AD7720 12pF 1k 1k AIN = 1.25V 1/2 OP275 1k 12pF 1k 1k 100nF 1/2 374k OP275 374k 220nF Figure 28. Single-Ended Analog Input for Bipolar Mode Operation 12pF 1k 1k AIN = 0.625V 1/2 OP275 12pF 1k 1k 1/2 ...
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Offset and Gain Calibration The analog inputs of the AD7720 can be configured to measure offset and gain errors. Pins MZERO and GC are used to config- ure the part. Before calibrating the device, the part should be reset so ...
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AD7720 0.006 (0.15) 0.002 (0.05) SEATING PLANE OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 28-Lead Thin Shrink Small Outline (RU-28) 0.386 (9.80) 0.378 (9.60 PIN 1 0.0433 (1.10) MAX 0.0118 (0.30) 0.0256 (0.65) 0.0079 (0.20) ...
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