ADC0805 NSC [National Semiconductor], ADC0805 Datasheet
ADC0805
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ADC0805 Summary of contents
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... ADC0801/ADC0802/ADC0803/ADC0804/ADC0805 8-Bit µP Compatible A/D Converters General Description The ADC0801, ADC0802, ADC0803, ADC0804 and ADC0805 are CMOS 8-bit successive approximation A/D converters that use a differential ladder — similar to the 256R products. These converters are designed to allow operation with the NSC800 and INS8080A derivative control bus with TRI-STATE ® ...
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... Typical Applications Part Number Adjusted ± ADC0801 ADC0802 ± ADC0803 ADC0804 ADC0805 www.national.com 8080 Interface DS005671-31 Error Specification (Includes Full-Scale, Zero Error, and Non-Linearity 2.500 Connection Full REF DC REF Scale (No Adjustments) (No Adjustments) ⁄ LSB 1 4 ± 1 ⁄ LSB 2 1 ⁄ ...
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... The following specifications apply for V CC Parameter ADC0801: Total Adjusted Error (Note 8) ADC0802: Total Unadjusted Error (Note 8) ADC0803: Total Adjusted Error (Note 8) ADC0804: Total Unadjusted Error (Note 8) ADC0805: Total Unadjusted Error (Note Input Resistance (Pin 9) REF Analog Input Voltage Range DC Common-Mode Error Power Supply Sensitivity ...
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AC Electrical Characteristics The following specifications apply for V CC Symbol Parameter C TRI-STATE Output OUT Capacitance (Data Buffers) CONTROL INPUTS [Note: CLK IN (Pin 4) is the input of a Schmitt trigger circuit and is therefore specified separately] V ...
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... Note 9: The V /2 pin is the center point of a two-resistor divider connected from V REF ADC0805, and in the ADC0804LCJ, each resistor is typically all versions of the ADC0804 except the ADC0804LCJ, each resistor is typically 2 Note 10: Human body model, 100 pF discharged through a 1.5 k Typical Performance Characteristics Logic Input Threshold Voltage vs ...
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TRI-STATE Test Circuits and Waveforms t 1H DS005671- DS005671-49 Timing Diagrams (All timing is measured from the 50% voltage points) www.national.com = DS005671- ...
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Timing Diagrams (All timing is measured from the 50% voltage points) (Continued) Note: Read strobe must occur 8 clock periods (8/f ) after assertion of interrupt to guarantee reset of INTR . CLK Typical Applications 6800 Interface Output Enable and ...
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Typical Applications (Continued) Absolute with a 2.500V Reference *For low power, see also LM385–2.5 Zero-Shift and Span Adjust: 2V www.national.com Absolute with a 5V Reference DS005671- Span Adjust DS005671-57 8 DS005671- DS005671-58 ...
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Typical Applications (Continued) Directly Converting a Low-Level Signal /2 = 256 mV V REF 1 mV Resolution with µP Controlled Range /2 = 128 mV V REF 1 LSB = +256 mV) DAC IN DAC ...
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Typical Applications (Continued) Self-Clocking Multiple A/Ds * Use a large R value to reduce loading at CLK R output. www.national.com Digitizing a Current Flow 100 kHz f DS005671-63 10 DS005671-62 External Clocking DS005671-64 1460 kHz CLK ...
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Typical Applications (Continued) Self-Clocking in Free-Running Mode DS005671-65 *After power-up, a momentary grounding of the WR input is needed to guarantee operation. Operating with “Automotive” Ratiometric Transducers (− 85% of ...
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Typical Applications (Continued) ± Handling 10V Analog Inputs *Beckman Instruments # 694-3-R10K resistor array µP Interfaced Temperature-to-Digital Converter *Circuit values shown are for 0˚C T +128˚ Can calibrate each sensor to allow easy replacement, then A/D can ...
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Typical Applications (Continued) ± Handling 5V Analog Inputs *Beckman Instruments # 694-3-R10K resistor array µP Interfaced Comparator with Hysteresis DS005671-35 Read-Only Interface DS005671-33 Protecting the Input Diodes are 1N914 13 DS005671-34 DS005671-9 www.national.com ...
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Typical Applications (Continued) A Low-Cost, 3-Decade Logarithmic Converter *LM389 transistors LM324A quad op amp www.national.com Analog Self-Test for a System DS005671-36 14 DS005671-37 ...
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Typical Applications (Continued) Noise Filtering the Analog Input = Uses Chebyshev implementation for steeper roll-off unity-gain, 2nd order, low-pass filter Adding a separate filter for each channel increases system response time if an analog multiplexer is ...
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Typical Applications (Continued) Note 11: Oversample whenever possible [keep fs Note 12: Consider the amplitude errors which are introduced within the passband of the filter. (Complete shutdown takes 30 seconds.) *Use ADC0801, 02 for lowest power consumption. ...
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Functional Description (Continued) Figure 2 shows a worst case error plot for the ADC0801. All center-valued inputs are guaranteed to produce the correct output codes and the adjacent risers are guaranteed to be ± no closer to the center-value points ...
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Functional Description Transfer Function DS005671-85 FIGURE 3. Clarifying the Error Specs of an A/D Converter 2.0 FUNCTIONAL DESCRIPTION The ADC0801 series contains a circuit equivalent of the 256R network. Analog switches are sequenced by succes- sive approximation logic to match ...
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Functional Description (Continued) Note 13: CS shown twice for clarity. Note 14: SAR = Successive Approximation Register. After the “1” is clocked through the 8-bit shift register (which completes the SAR search) it appears as the input to the D-type ...
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Functional Description 2.2 Analog Differential Voltage Inputs and Common-Mode Rejection This A/D has additional applications flexibility due to the ana- log differential voltage input. The V (−) input (pin 7) can be IN used to automatically subtract a fixed voltage ...
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... A/D con- verter and therefore cancels out in the final digital output or an adjusted code. The ADC0805 is specified particularly for use in ratio- metric applications with no adjustments required. In absolute conversion applications, both the initial value and the tem- perature stability of the reference voltage are important fac- tors in the accuracy of the A/D converter ...
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Functional Description DS005671-87 a) Analog Input Signal Example FIGURE 7. Adapting the A/D Analog Input Voltages to Match an Arbitrary Input Signal Range 2.5 Errors and Reference Voltage Adjustments 2.5.1 Zero Error The zero of the A/D does not require ...
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Functional Description (Continued) DS005671-17 FIGURE 8. Self-Clocking the A/D Heavy capacitive or DC loading of the clock R pin should be avoided as this will disturb normal converter operation. Loads less than 50 pF, such as driving ...
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Functional Description FIGURE 9. Basic A/D Tester www.national.com For a higher speed test system obtain plotted data, a (Continued) digital-to-analog converter is needed for the test set-up. An accurate 10-bit DAC can serve as the precision voltage source ...
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Functional Description (Continued) FIGURE 10. A/D Tester with Analog Error Output TABLE 1. DECODING THE DIGITAL OUTPUT LEDs HEX BINARY MS GROUP ...
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Functional Description Note 16: * Pin numbers for the DP8228 system controller, others are INS8080A. Note 17: Pin 23 of the INS8228 must be tied to +12V through instruction when an interrupt is acknowledged as required by ...
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Functional Description (Continued) SAMPLE PROGRAM FOR Figure 12 ADC0801–INS8080A CPU INTERFACE Note 18: The stack pointer must be dimensioned because a RST 7 instruction pushes the PC onto the stack. Note 19: All address used were arbitrarily chosen. The standard ...
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Functional Description SAMPLE PROGRAM FOR Figure 13 INS8048 INTERFACE 4.2 Interfacing the Z-80 The Z-80 control bus is slightly different from that of the 8080. General RD and WR strobes are provided and sepa- rate memory request, MREQ, and I/O ...
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Functional Description (Continued) ing I/O input instructions. For example, MUX channel selec- tion for the A/D can be accomplished with this operating mode. 4.3 Interfacing 6800 Microprocessor Derivatives (6502, etc.) The control bus for the 6800 microprocessor derivatives does not ...
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Functional Description SAMPLE PROGRAM FOR Figure 15 ADC0801-MC6800 CPU INTERFACE Note 22: In order for the microprocessor to service subroutines and interrupts, the stack pointer must be dimensioned in the user’s program. www.national.com (Continued) FIGURE 16. ADC0801–MC6820 PIA Interface 30 ...
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Functional Description (Continued) SAMPLE PROGRAM FOR Figure 16 ADC0801–MC6820 PIA INTERFACE The following schematic and sample subroutine (DATA IN) may be used to interface (up to) 8 ADC0801’s directly to the MC6800 CPU. This scheme can easily be extended to ...
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Functional Description Note 23: Numbers in parentheses refer to MC6800 CPU pin out. Note 24: Numbers of letters in brackets refer to standard M6800 system common bus code. FIGURE 17. Interfacing Multiple A/ MC6800 System www.national.com (Continued) 32 ...
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Functional Description (Continued) SAMPLE PROGRAM FOR Figure 17 INTERFACING MULTIPLE A/D’ MC6800 SYSTEM SAMPLE PROGRAM FOR Figure 17 INTERFACING MULTIPLE A/D’ MC6800 SYSTEM Note 25: In order for the microprocessor to service subroutines and interrupts, the ...
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Functional Description any output of Port B will source current into node V raising the voltage at V and making the output differential X more negative. Conversely, a logic “0” (0V) will pull current out of node V and decrease ...
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Functional Description (Continued) FIGURE 19. Microprocessor Interface Circuitry for Differential Preamp A flow chart for the zeroing subroutine is shown in Figure must be noted that the ADC0801 series will output an all zero code when it ...
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Functional Description FIGURE 20. Flow Chart for Auto-Zero Routine www.national.com (Continued) 36 DS005671-28 ...
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Functional Description (Continued) Note 29: All numerical values are hexadecimal representations. FIGURE 21. Software for Auto-Zeroed Differential A/D 5.3 Multiple A/D Converters in a Z-80 Interrupt Driven Mode (Continued) The following notes apply: • assumed that the CPU ...
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Functional Description HEX PORT ADDRESS PERIPHERAL 00 MM74C374 8-bit flip-flop A/D 3 FIGURE 22. Multiple A/Ds with Z-80 Type Microprocessor www.national.com (Continued) HEX PORT ADDRESS This port address also ...
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Functional Description (Continued) 39 DS005671-A6 www.national.com ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number ADC0802LCWM or ADC0804LCWM ADC0803LCN, ADC0804LCN or ADC0805LCN www.national.com SO Package (M) NS Package Number M20B Molded Dual-In-Line Package (N) Order Number ADC0801LCN, ADC0802LCN, NS Package Number N20A 40 ...
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LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support ...