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ADC0801LC Datasheet

Download or read online National Semiconductor ADC0801LC 8-Bit µP Compatible A/D Converters, Package: Mdip, Pin Nb=20 pdf datasheet.



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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 output latches directly
driving the data bus. These A/Ds appear like memory loca-
tions or I/O ports to the microprocessor and no interfacing
logic is needed.
Differential analog voltage inputs allow increasing the
common-mode rejection and offsetting the analog zero input
voltage value. In addition, the voltage reference input can be
adjusted to allow encoding any smaller analog voltage span
to the full 8 bits of resolution.
Features
n Compatible with 8080 µP derivatives — no interfacing
logic needed - access time - 135 ns
n Easy interface to all microprocessors, or operates “stand
alone”
Connection Diagram
Ordering Information
TEMP RANGE
±
1
Bit Adjusted
4
±
ERROR
1
Bit Unadjusted
2
±
1
Bit Adjusted
2
±
1Bit Unadjusted
PACKAGE OUTLINE
Z-80
®
is a registered trademark of Zilog Corp.
© 2001 National Semiconductor Corporation
n Differential analog voltage inputs
n Logic inputs and outputs meet both MOS and TTL
voltage level specifications
n Works with 2.5V (LM336) voltage reference
potentiometric
n On-chip clock generator
n 0V to 5V analog input voltage range with single 5V
supply
n No zero adjust required
n 0.3" standard width 20-pin DIP package
n 20-pin molded chip carrier or small outline package
n Operates ratiometrically or with 5 V
analog span adjusted voltage reference
Key Specifications
n Resolution
n Total error
n Conversion time
ADC080X
Dual-In-Line and Small Outline (SO) Packages
DS005671-30
See Ordering Information
0˚C TO 70˚C
0˚C TO 70˚C
ADC0802LCWM
ADC0804LCWM
ADC0804LCN
M20B — Small
Outline
DS005671
November 1999
, 2.5 V
, or
DC
DC
8 bits
±
±
±
1
LSB,
1
LSB and
1 LSB
4
2
100 µs
−40˚C TO +85˚C
ADC0801LCN
ADC0802LCN
ADC0803LCN
ADC0805LCN/ADC0804LCJ
N20A — Molded DIP
www.national.com

Summary of Contents

Page 1

... TO 70C ADC0802LCWM ADC0804LCWM ADC0804LCN M20B Small Outline DS005671 November 1999 , 2 bits ± ± ± 1 LSB, 1 LSB and 1 LSB 4 2 100 µs 40C TO 85C ADC0801LCN ADC0802LCN ADC0803LCN ADC0805LCN/ADC0804LCJ N20A Molded DIP www.national.com ...

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Typical Applications Part Number ADC0801 ADC0802 ADC0803 ADC0804 ADC0805 www.national.com 8080 Interface Error Specification (Includes Full-Scale, Zero Error, and Non-Linearity) Full- V /22.500 V V REF DC REF Scale (No Adjustments) (No Adjustments) Adjusted ± 1 LSB 4 ± ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (V ) (Note 3) CC Voltage Logic Control Inputs At Other Input and Outputs Lead Temp. (Soldering, 10 seconds) Dual-In-Line Package (plastic) Dual-In-Line Package (ceramic) ...

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AC Electrical Characteristics The following specifications apply for V 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 (1) ...

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AC Electrical Characteristics Note 7: The CS input is assumed to bracket the WR strobe input and therefore timing is dependent on the WR pulse width. An arbitrarily wide pulse width will hold the converter in a reset mode and ...

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TRI-STATE Test Circuits and Waveforms DS005671-49 Timing Diagrams (All timing is measured from the 50% voltage points) www.national.com DS005671- DS005671-48 ...

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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 Typical Applications 6800 Interface Output Enable and Reset with INTR ) after assertion of interrupt to guarantee reset of ...

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Typical Applications (Continued) Absolute with a 2.500V Reference For low power, see also LM3852.5 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 V /2256 mV REF V /2128 mV REF 1 LSB 256 mV) DAC IN DAC < 2.5V DAC DS005671- Resolution with µP Controlled Range ...

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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 After power-up, a momentary grounding of the WR input is needed to guarantee operation. Operating with Automotive Ratiometric Transducers V () XDR ...

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Typical Applications (Continued) ± Handling 10V Analog Inputs Beckman Instruments # 694-3-R10K resistor array Circuit values shown are for 0C T 128˚ Can calibrate each sensor to allow easy replacement, then A/D can be calibrated with a ...

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Typical Applications (Continued) ± Handling 5V Analog Inputs Beckman Instruments # 694-3-R10K resistor array µP Interfaced Comparator with Hysteresis DS005671-33 Diodes are 1N914 DS005671-35 13 Read-Only Interface DS005671-34 Protecting the Input DS005671-9 www.national.com ...

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Typical Applications (Continued) LM389 transistors LM324A quad op amp www.national.com Analog Self-Test for a System A Low-Cost, 3-Decade Logarithmic Converter 14 DS005671-36 DS005671-37 ...

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Typical Applications (Continued) Noise Filtering the Analog Input f 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 used ...

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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 ± 1 LSB from the ideal center-values. Each tread (the range 2 of analog input voltage that provides the same digital output code) is therefore 1 LSB wide. Figure 2 shows a worst case error plot for ...

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Functional Description Transfer Function 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 the ...

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Functional Description 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 latch, ...

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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 analog differential voltage input. The V be used to automatically subtract a fixed voltage value from the input reading (tare correction). ...

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Functional Description wire. A 100 series resistor can be used to isolate this capacitor both the R and C are placed outside the feed- back loop from the output amp, if used. 2.3.4 Noise The ...

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Functional Description 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 adjustment. ...

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Functional Description 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 A/D converter ...

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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 TABLE 1. DECODING THE DIGITAL OUTPUT LEDs HEX BINARY MS GROUP 3 ...

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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 SAMPLE PROGRAM FOR Figure 12 ADC0801INS8080A 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 control ...

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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 A15) during I/O input instructions. For example, MUX chan- nel selection 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 users program. www.national.com (Continued) FIGURE 16. ADC0801MC6820 PIA Interface 30 ...

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Functional Description SAMPLE PROGRAM FOR Figure 16 ADC0801MC6820 PIA INTERFACE The following schematic and sample subroutine (DATA IN) may be used to interface (up to) 8 ADC0801s directly to the MC6800 CPU. This scheme can easily be extended to allow ...

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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 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 stack ...

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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 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 converts ...

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Functional Description www.national.com (Continued) FIGURE 20. Flow Chart for Auto-Zero Routine 36 DS005671-28 ...

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Functional Description 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 automatically ...

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Functional Description HEX PORT ADDRESS 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 PERIPHERAL This port address also serves as the A/D ...

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Functional Description (Continued) 39 DS005671-A6 www.national.com ...

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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted SO Package (M) Order Number ADC0802LCWM or ADC0804LCWM NS Package Number M20B Molded Dual-In-Line Package (N) Order Number ADC0801LCN, ADC0802LCN, ADC0803LCN, ADC0804LCN or ADC0805LCN NS Package Number N20A 40 ...

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... NATIONALS 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 devices or systems are devices or systems which, (a) are intended for surgical implant ...

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