AD7895 Analog Devices, AD7895 Datasheet
AD7895
Specifications of AD7895
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AD7895 Summary of contents
Page 1
... Low Power max 14-Bit Pin Compatible Upgrade (AD7894) GENERAL DESCRIPTION The AD7895 is a fast 12-bit ADC that operates from a single +5 V supply and is housed in a small 8-pin mini-DIP and 8-pin SOIC. The part contains a 3.8 s 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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... Minimum Resolution for which No Missing Codes are Guaranteed 3 Relative Accuracy 3 Differential Nonlinearity 3 Positive Full-Scale Error AD7895-2 Unipolar Offset Error AD7895-10, AD7895-3 Only 3 Negative Full-Scale Error Bipolar Zero Error ANALOG INPUT AD7895-10 Input Voltage Range Input Resistance AD7895-3 Input Voltage Range Input Resistance ...
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... C unless otherwise noted GND . . . . . . . . . . . . . . . . . . . . . . . . . . –0 Analog Input Voltage to GND AD7895- AD7895-2, AD7895 –5 V, +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 AD7895. 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 that data can be accepted on the falling edge when a fast serial clock is used. The serial clock input should be taken low at the end of the serial data transmission ...
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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 12-bit converter, this is 74 dB. Total Harmonic Distortion Total harmonic distortion (THD) is the ratio of the rms sum of harmonics to the fundamental. For the AD7895 defined as ...
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... This input is benign with no dynamic charging currents, as the resistor stage is followed by a high input imped- ance stage of the track/hold amplifier. For the AD7895-10 7.5 k and For the AD7895- 6.5 k and R3 is open circuit. For the AD7895-10 and AD7895-3, the designed code transi- tions occur on successive integer LSB values (i ...
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... CONVST, and new data from this conversion is available in the output register of the AD7895 3.8 s later. Once the read operation has taken place, a further 300 ns should be allowed before the next falling edge of CONVST to optimize the settling of the track/hold amplifier before the next conversion is initi- ated ...
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... The serial clock input does not have to be continuous during the serial read operation. The sixteen bits of data (four leading zeros and 12 bit conversion result) can be read from the AD7895 in a number of bytes. The AD7895 counts the serial clock edges to know which bit from the output register should be placed on the SDATA output ...
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... AD7895. A simple AND function on this port bit and the serial clock from the 8XL51 will provide this function. The port bit should be high to select the AD7895 and low when it is not selected ...
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... SCLK1 to be read correctly by the ADSP-2103/5. The data access time for the AD7895 (A, B versions)) from the rising edge of its SCLK input. Assuming propagation delay through the external AND gate, the high time of the SCLK1 output of the ADSP-2105 must be ( +10 +10) ns, i ...
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... Spurious Noise, and Intermodulation Distortion are all specified. Figure 11 shows a typical FFT plot kHz input after being digitized by the AD7895 operating at a 198.656 kHz sampling rate. The Signal to (Noise + Distor- tion) Ratio is 73.04 dB, and the Total Harmonic Distortion is – ...
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... AD7895 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). Plastic DIP (N-8) 0.430 (10.92) 0.348 (8.84 0.280 (7.11) 0.240 (6.10 0.325 (8.25) 0.300 (7.62) 0.060 (1.52) PIN 1 0.015 (0.38) 0.210 (5.33) MAX 0.130 (3.30) 0.160 (4.06) MIN 0.115 (2.93) SEATING 0.022 (0.558) 0.100 0.070 (1.77) PLANE (2.54) 0.014 (0.356) 0.045 (1.15) BSC SOIC (SO-8) 0.1968 (5.00) 0.1890 (4.80 0.2440 (6.20) ...