AD976 Analog Devices, AD976 Datasheet
AD976
Specifications of AD976
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AD976 Summary of contents
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... The AD976/AD976A is a high speed (100 kSPS/200 kSPS throughput rates respectively), 16-bit ADC based on a switched capacitor architecture. 2. Single-Supply Operation. The AD976/AD976A operates from a single 5 V supply and dissipates only 100 mW max. 3. Comprehensive DC and AC Specifications. The AD976/AD976A is factory calibrated and fully tested for SNR and THD as well as the traditional specifications of offset, gain and linearity ...
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... Typical rms noise at worst case transitions and temperatures. 3 Measured with fixed resistors as shown in Figure 5 (AD976) and Figure 6 (AD976A). Adjustable to zero as shown in Figure 7. 4 Full-scale error is expressed as the % difference between the actual full-scale code transition voltage and the ideal full-scale transition voltage and includes the effect of offset error. The full-scale error is the worst case of either the – ...
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... Typical rms noise at worst case transitions and temperatures. 3 Measured with fixed resistors as shown in Figure 5 (AD976) and Figure 6 (AD976A). Adjustable to zero as shown in Figure 7. 4 Full-scale error is expressed as the % difference between the actual full-scale code transition voltage and the ideal full-scale transition voltage and includes the effect of offset error. The full-scale error is the worst case of either the – ...
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... TIMING SPECIFICATIONS (AD976A: F Convert Pulsewidth Data Valid Delay after R/C Low (AD976A/AD976) BUSY Delay from R/C Low BUSY Low (AD976A/AD976) BUSY Delay after End of Conversion (AD976A/AD976) Aperture Delay Conversion Time (AD976A/AD976) Acquisition Time Bus Relinquish Time BUSY Delay after Data Valid (AD976A/AD976) Previous Data Valid after R/C Low (AD976A/AD976) ...
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... 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. Although the AD976/AD976A features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... AD976/AD976A Pin No. Mnemonic Description 1 V Analog Input. Connect a 200 IN input range AGND1 Analog Ground. Used as the ground reference point for the REF pin. 3 REF Reference Input/Output. The internal +2.5 V reference is available at this pin. Alternatively, an external reference can be used to override the internal reference. In either case, connect a 2.2 F tantalum capacitor between REF and AGND1 ...
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... ADC output spectrum ( value of the fundamental. Normally, the value of this specification will be determined by the largest harmonic in the spectrum. The typical SPFD for the AD976/AD976A is –100 dB and can be seen in Figure 10. FUNCTIONAL DESCRIPTION The AD976/AD976A is a high speed, low power, 16-bit sam- pling, analog-to-digital converter that can operate from a single +5 volt power supply ...
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... ADC. Once these two pulses are applied, BUSY will go low and remain low until a conver- sion is complete. After a maximum (AD976A only), BUSY will again return high, and parallel data will be valid on the ADC outputs. To achieve the maximum 100 kHz/200 kHz throughput rate of the part, the negative going R/C and CS control signals should be applied every 5 s (AD976A) ...
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... AD976A, care should be taken in the selection of the drive circuitry op amp. Figure 6 shows the analog input section for the AD976A when operating with an internal reference only. Figure 9 shows the analog input section for both the AD976 and the AD976A when operating with an external reference. REV. C ...
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... Tables I and II illustrate the worst case range for Bipolar Zero (offset) error and Full-Scale (gain) error for the AD976 and the AD976A. All error terms are with respect to the A/D (i.e., a negative offset in the table would have to be corrected with an externally applied positive voltage). ...
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... By distributing noise over a wider frequency range, the noise density in the frequency band of interest can be reduced. For example, if the required input bandwidth is 50 kHz, the AD976A could be oversampled by a factor of 2. This would yield improvement in the effective SNR performance. –10 – ...
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... AD976/AD976A 100% 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2 OUTPUT CODE – K Figure 11. INL Plot 100% 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2 OUTPUT CODE – K Figure 12. DNL Plot –55 25 DEGREES CELSIUS Figure 13. Reference Drift ...
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... ADC, a range of output codes may occur for a given input voltage. Thus, when a dc signal is applied to the AD976/AD976A input, and 10,000 conversions are recorded, the result will be a distri- bution of codes as shown in Figure 19. This histogram shows a bell-shaped curve consistent with the Gaussian nature of ther- mal noise ...
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... This DB15 will effectively lower the supplies impedance presented to the DB0 AD976/AD976A V of these spikes. Decoupling capacitors, typically 0.1 F, should be placed close to the power supply pins of the AD976/AD976A to minimize any inductance between the capacitors and the V and V ANA DIG The AD976/AD976A may be operated from a single +5 V sup- ply ...
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... ADC. The digital ground pin, DGND, is the reference point for all of the digital signals that control the AD976/AD976A. The AD976/AD976A can be powered with two separate power supplies or with a single analog supply. When the system digital ...
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... AD976/AD976A 0.210 (5.33) 0.150 (3.81) 0.115 (2.92) 0.0118 (0.30) 0.0040 (0.10) 0.078 (1.98) 0.068 (1.73) 0.008 (0.203) 0.002 (0.050) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 28-Lead 300 mil Plastic DIP (N-28B) 1.425 (36.195) 1.385 (35.179 0.280 (7.11) 0.240 (6.10 PIN 1 0.015 (0.381) MIN MAX SEATING PLANE 0.022 (0.558) ...