AD7769JP Analog Devices Inc, AD7769JP Datasheet
AD7769JP
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AD7769JP Summary of contents
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FEATURES Two-Channel, 8-Bit 2.5 s ADC Two 8-Bit, 2.5 s DACs with Output Amplifiers Span and Offset of ADC and DAC Independently Adjustable Low Power APPLICATIONS Winchester Disk Servo Controllers Floppy Disk Microstepping Closed Loop Servo Systems GENERAL DESCRIPTION ...
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AD7769–SPECIFICATIONS ( ADC SPECIFICATIONS V SWING Parameter J Version DC ACCURACY Resolution 8 Relative Accuracy 1 Differential Nonlinearity 1 Bias Offset Error + 3.0 MIN MAX Bias Offset Match +25 C ...
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DACA, DACB SPECIFICATIONS Parameter J Version A Version Units STATIC PERFORMANCE Resolution 8 Relative Accuracy 1 Differential Nonlinearity 1 Bias Offset Error + 2.5 MIN MAX Bias Offset Match + ...
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AD7769 TIMING CHARACTERISTICS Parameter ADC /DAC CONTROL TIMING Setup Time Hold Time ADC/DAC to WR Setup Time ADC/DAC to WR Hold Time CHA/CHB to WR Setup Time CHA/CHB to WR Hold Time WR Pulse ...
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... Although the AD7769 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. ORDERING GUIDE Temperature Model Range AD7769JN +70 C AD7769JP +70 C AD7769AN – +85 C AD7769AP – + Plastic DIP Plastic Leaded Chip Carrier. DIP REV. A Power Dissipation (Any Package) to +75 C ...
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AD7769 PIN FUNCTION DESCRIPTION Pin Mnemonic Description 1 V +12 V Power Supply. This powers the analog circuitry Power Supply. This powers the logic circuitry. CC 3–10 DB7–DB0 Input/Output Data Bus. A bidirectional data port ...
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Plus and Minus Full-Scale Error The ADC and DACs in the AD7769 can be considered as de- vices with bipolar (plus and minus) input ranges, but referred to V instead of AGND. Plus Full-Scale Error for the ADC is the ...
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AD7769 CIRCUIT DESCRIPTION Analog Inputs and Outputs The AD7769 provides the analog-to-digital and digital-to-analog conversion functions required between the microcontroller and the servo power amplifier in digital servo systems intended primarily for closed loop head positioning in Winchester ...
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Figure 8. Operating Waveforms Using External Clock Following the “hold” on the analog input, the MSB decision is made approximately 50 ns after the next falling edge of the in- put CLK. The succeeding bit decisions are made approxi- mately ...
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AD7769 held low but CS is taken high during the conversion, the device will be de-selected and DB0–DB7 will revert to their high impedance state. This will not affect completion of the conversion, but the data ...
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This is for an ideal part with no differential or integral linearity errors. These errors will cause a degradation in SNR. By work- ing backwards from the above equation possible to get a measure of ADC performance expressed ...
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AD7769 Conversion is initiated on the selected AD7769 ADC channel using a single I/O instruction, <OUT ADC, A>. The processor then polls INT until it goes low before reading the conversion result using an <IN A, ADC> instruction. Writing data ...
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APPLICATIONS The AD7769 analog I/O port is used to convert servo related signals between the analog and digital domains. The input structure of the two-channel ADC makes it very easy to convert the typical output signals provided by a servo ...
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AD7769 Increased Resolution DAC Output Since both V (DAC) and V (DAC) are common to BIAS SWING both output channels, the full-scale output voltages of both channels are nominally identical. However, by adding an exter- nal op amp and scaling ...
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Figure 28. Generating a Software Programmable V (DAC) For example, with a fixed input swing voltage of 2.5 V, the pro- grammable span via DAC follows (DAC) = 2.08 B SWING D = ...
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Multichannel Expansion In some applications, more than two analog input channels are required to be converted by the ADC. Figure 31 shows a circuit configuration for such an application. The ADG528A is a latched, B-channel analog multiplexer that is ideally ...