AD7894 Analog Devices, AD7894 Datasheet
AD7894
Specifications of AD7894
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AD7894 Summary of contents
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... Low Power Typ Pin Compatible Upgrade of 12-Bit AD7895 GENERAL DESCRIPTION The AD7894 is a fast, 14-bit ADC that operates from a single +5 V supply and is housed in a small 8-lead SOIC. The part contains successive approximation A/D converter, an on- chip track/hold amplifier, an on-chip clock and a high speed serial interface ...
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... Resolution Minimum Resolution for Which No Missing Codes Are Guaranteed 3 Relative Accuracy 3 Differential Nonlinearity AD7894-2 3 Positive Gain Error Unipolar Offset Error AD7894-10, AD7894-3 Only 3 Positive Gain Error 3 Negative Gain Error Bipolar Zero Error ANALOG INPUT AD7894-10 Input Voltage Range Input Current AD7894-3 ...
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... GND . . . . . . . . . . . . . . . . . . . . . . . . . . –0 Analog Input Voltage to GND AD7894- AD7894 AD7894 – +10 V Reference Input Voltage to GND . . . . –0 Digital Input Voltage to GND . . . . . . . –0 Digital Output Voltage to GND . . . . . –0 Operating Temperature Range Commercial (A, B Versions – +85 C Storage Temperature Range . . . . . . . . . . . – ...
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... SCLK Serial Clock Input. An external serial clock is applied to this input to obtain serial data from the AD7894. A new serial data bit is clocked out on the falling edge of this serial clock. Data is guaranteed valid for 10 ns after this falling edge so data can be accepted on the falling edge when a fast serial clock is used. ...
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... N-bit converter with a sine wave input is given by: Signal to (Noise + Distortion) = (6. 1.76) dB Thus for a 14-bit converter, this is 86.04 dB. Total Harmonic Distortion Total harmonic distortion (THD) is the ratio of the rms sum of harmonics to the fundamental. For the AD7894 defined as ...
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... For the AD7894-10 and For the AD7894- and R3 is open circuit. The current flowing in the analog input is di- rectly related to the analog input voltage. The maximum input current flows when the analog input is at negative full scale ...
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... AD7894. In the se- quence shown, conversion is initiated on the falling edge of CONVST and new data from this conversion is available in the output register of the AD7894 5 s later. Once the read opera- tion has taken place, a further 250 ns should be allowed before CONVST ...
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... Mode 1 Operation. Serial Interface The serial interface to the AD7894 consists of just three wires, a serial clock input (SCLK) and the serial data output (SDATA) and a conversion status output (BUSY). This allows for an t ...
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... AD7894. A simple AND function on this port bit and the serial clock from the 68L11 will provide this function. The port bit should be high to select the AD7894 and low when it is not selected ...
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... ADSP-2101/5 before it is applied to the SCLK input of the AD7894. The RFS1 output is configured for active high operation. The BUSY line from the AD7894 is connected to the IRQ2 line of the ADSP-2101/5 so that at the end of conversion an interrupt is generated telling the ADSP-2101/5 to initiate a read operation. ...
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... Dynamic Performance (Mode 1 Only) With a conversion time the AD7894 is ideal for wide bandwidth signal processing applications. These applications require information on the ADC’s effect on the spectral con- tent of the input signal. Signal to (Noise + Distortion), Total Harmonic Distortion, Peak Harmonic or Spurious Noise and Intermodulation Distortion are all specified ...
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... AD7894 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 8-Lead Narrow Body SOIC (SO-8) 0.1968 (5.00) 0.1890 (4.80 0.1574 (4.00) 0.2440 (6.20 0.1497 (3.80) 0.2284 (5.80) PIN 1 0.0688 (1.75) 0.0196 (0.50) 0.0098 (0.25) 0.0532 (1.35) 0.0099 (0.25) 0.0040 (0.10) 8 0.0500 0.0192 (0.49) 0 SEATING 0.0098 (0.25) 0.0500 (1.27) (1.27) 0.0138 (0.35) PLANE BSC 0.0075 (0.19) 0.0160 (0.41) –12– 45 REV. 0 ...