ADC0809 National Semiconductor Corporation, ADC0809 Datasheet
ADC0809
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ADC0809 Summary of contents
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... Easy interfacing to microprocessors is provided by the latched and decoded multiplexer address inputs and latched TTL TRI-STATE outputs. The design of the ADC0808, ADC0809 has been optimized by incorporating the most desirable aspects of several A/D conversion techniques. The ADC0808, ADC0809 offers high speed, high accuracy, minimal temperature dependence, ex- cellent long-term accuracy and repeatability, and consumes minimal power ...
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... Connection Diagrams Dual-In-Line Package Order Number ADC0808CCN or ADC0809CCN See NS Package J28A or N28A Ordering Information Temperature Range Package Outline ±½ LSB Unadjusted Error ±1 LSB Unadjusted www.national.com 567211 Order Number ADC0808CCV or ADC0809CCV −40°C to +85°C N28A Molded DIP V28A Molded Chip Carrier ...
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... REF(+) Voltage, Center of Ladder V Voltage, Bottom of Ladder REF(−) I Comparator Input Current IN Electrical Characteristics – Digital Levels and DC Specifications Digital Levels and DC Specifications: ADC0808CCN, ADC0808CCV, ADC0809CCN and ADC0809CCV, 4.75 ≤ ≤ −40°C T +85°C unless otherwise noted A Symbol Parameter ANALOG MULTIPLEXER ...
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Symbol Parameter Logical “1” Input Current (The Control I IN(1) Inputs) Logical “0” Input Current (The Control I IN(0) Inputs) I Supply Current CC DATA OUTPUTS AND EOC (INTERRUPT) V Logical “1” Output Voltage OUT(1) V Logical “0” Output Voltage ...
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... The successive approximation register (SAR) performs 8 it- erations to approximate the input voltage. For any SAR type converter, n-iterations are required for an n-bit converter. Fig- ure 2 shows a typical example of a 3-bit converter. In the ADC0808, ADC0809, the approximation technique is extend bits using the 256R network ...
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FIGURE 2. 3-Bit A/D Transfer Curve www.national.com FIGURE 1. Resistor Ladder and Switch Tree 567213 FIGURE 3. 3-Bit A/D Absolute Accuracy Curve FIGURE 4. Typical Error Curve 6 567202 567214 567215 ...
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Timing Diagram FIGURE 5. 7 567204 www.national.com ...
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Typical Performance Characteristics www.national.com 567216 FIGURE 6. Comparator I vs =5V) CC REF 567217 FIGURE 7. Multiplexer R vs =5V) CC REF 8 ...
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... L Applications Information OPERATION 1.0 RATIOMETRIC CONVERSION The ADC0808, ADC0809 is designed as a complete Data Acquisition System (DAS) for ratiometric conversion systems. In ratiometric systems, the physical variable being measured is expressed as a percentage of full-scale which is not nec- essarily related to an absolute standard. The voltage input to ...
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Figure 10 shows a ground referenced system with a separate supply and reference. In this system, the supply must be trimmed to match the reference voltage. For instance The ADC0808 needs less than a milliamp of supply current ...
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FIGURE 11. Ground Referenced Conversion System with Reference Generating V CC FIGURE 12. Typical Reference and Supply Circuit 11 567225 Supply 567226 www.national.com ...
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*Ratiometric transducers 3.0 CONVERTER EQUATIONS The transition between adjacent codes N and N+1 is given by: The center of an output code N is given by: The output code N for an arbitrary input are the ...
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Typical Application *Address latches needed for 8085 and SC/MP interfacing the ADC0808 to a microprocessor PROCESSOR 8080 MEMR 8085 RD Z-80 RD SC/MP NRDS 6800 VMA•φ2•R/W TABLE 2. Microprocessor Interface Table READ WRITE INTERRUPT (COMMENT) MEMW INTR (Thru RST Circuit) ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted Molded Dual-In-Line Package (N) Order Number ADC0808CCN or ADC0809CCN NS Package Number N28B Molded Chip Carrier (V) Order Number ADC0808CCV or ADC0809CCV NS Package Number V28A 14 ...
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15 www.national.com ...
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... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...