AD774B Analog Devices, AD774B Datasheet

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... Analog Operation: The precision, laser-trimmed scaling and bipolar offset resistors provide four calibrated ranges +10 V and 0 to +20 V unipolar; – and – +10 V bipolar. The AD674B and AD774B operate and power supplies. 3. Flexible Digital Interface: On-chip multiple-mode three-state output buffers and interface logic allow direct connection to most microprocessors ...

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... AD674B/AD774B—SPECIFICATIONS 10 –15 V 10% or –12 V LOGIC EE Model (AD674B or AD774B) RESOLUTION LINEARITY ERROR @ + MIN MAX DIFFERENTIAL LINEARITY ERROR (Minimum Resolution for Which No Missing Codes are Guaranteed) 1 UNIPOLAR OFFSET @ + BIPOLAR OFFSET @ +25 C FULL-SCALE CALIBRATION ERROR (with Fixed 50 Resistor from REF OUT to REF IN) ...

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... AD674B/AD774B T Grade Typ Max Units 12 Bits 1/2 LSB 1 LSB Bits 2 LSB 3 LSB 0.1 0.125 % of FS +125 C 1 LSB 2 LSB 7 LSB 1 LSB 1/2 LSB LSB 1 +5 Volts +10 Volts ...

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... Symbol Min Typ Max Min Typ Max Units Conversion Time 8-Bit Cycle (AD674B 12-Bit Cycle (AD674B 8-Bit Cycle (AD774B 12-Bit Cycle (AD774B STS Delay from CE t DSC CE Pulse Width t 50 HEC Setup t 50 SSC CS Low During CE High ...

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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 AD674B/AD774B 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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... Thus every code must have a finite width. The AD674B and AD774B guarantee no missing codes to 12-bit resolution, requiring that all 4096 codes must be present over the entire operating temperature ranges ...

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... Analog Output DI = Digital Input DO = Digital Output P = Power REV. B AD674B AND AD774B PIN DESCRIPTION is Active HIGH during a convert start, a shorter 8-bit conversion cycle 0 = HIGH enables DB3-DB0 and sets DB7-DB4 = 0. 0 resistor to REF OUT for bipolar operation or to Analog is HIGH HIGH; they are disabled when A 0 should not be connected ...

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... AD711 sample-hold amplifier is required, the monolithic AD585 or AD781 is recommended, with the output buffer driving the AD674B or AD774B input directly. A better alternative is the AD1674 which sampling ADC in the same pinout as the AD574A, AD674A or AD774B and is functionally equivalent ...

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... Pin 14. UNIPOLAR CALIBRATION The connections for unipolar ranges are shown in Figure 7. The AD674B or AD774B is trimmed to a nominal 1/2 LSB offset so that the exact analog input for a given code will be in the middle of that code (halfway between the transitions to the codes above and below it) ...

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... CS R 12/8 CONTROL LOGIC The AD674B and AD774B contain on-chip logic to provide conversion initiation and data read operations from signals commonly available in microprocessor systems; this internal logic circuitry is shown in Figure 9. The control signals CE, CS, and R/C control the operation of the converter. The state of R/C when CE and CS are both as- serted determines whether a data read (R convert (R progress ...

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... ADCs take longer than one instruction cycle to complete a conversion. Valid data can, of course, only be read after the conversion is complete. The AD674B and AD774B provide an output signal (STS) which indicates when a conversion is in progress. This signal can be polled by the processor by reading it through an external three- state buffer (or other input port) ...

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... AD674B/AD774B 0.085 (2.16) 0.200 (5.080) MAX OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 28-Pin Ceramic DIP Package (D-28) 0.050 (12.83 0.59 + – 0.01 (14.98 1.42 (36.07) 0.095 (2.41) 1.40 (35.56) 0.050 + 0.010 – (1.27) + 0.1 (2.54) 0.017 0.003 – + – 0.047 0.007 (0.43) (1.19) 28-Lead Plastic DIP Package (N-28A 0.550 (13.97) 0.530 (13.462 1.450 (36.83) 1.440 (36.576) ...