<thead id="4hmw4"></thead>
  1. <noscript id="4hmw4"><pre id="4hmw4"></pre></noscript>
    參數資料
    型號: TC7136ARCLW
    元件分類: ADC
    英文描述: 1-CH DUAL-SLOPE ADC, PQCC44
    封裝: PLASTIC, LCC-44
    文件頁數: 11/15頁
    文件大?。?/td> 134K
    代理商: TC7136ARCLW
    5
    Low Power 3-1/2 Digit Analog-To-
    Digital Converters
    TC7136
    TC7136A
    TC7136-6
    10/18/96
    2001 Microchip Technology Inc.
    DS21461A
    GENERAL THEORY OF OPERATION
    (All Pin designations refer to 40-Pin Dip)
    Dual-Slope Conversion Principles
    The TC7136/A is a dual-slope, integrating analog-to-
    digital converter. An understanding of the dual-slope con-
    version technique will aid in following detailed TC7136/A
    operational theory.
    The conventional dual-slope converter measurement
    cycle has two distinct phases:
    (1) Input signal integration
    (2) Reference voltage integration (deintegration)
    The input signal being converted is integrated for a fixed
    time period (tSI), measured by counting clock pulses. An
    opposite polarity constant reference voltage is then inte-
    grated until the integrator output voltage returns to zero. The
    reference integration time is directly proportional to the input
    signal (tRI).
    In a simple dual-slope converter, a complete conversion
    requires the integrator output to "ramp-up" and "ramp-
    down."
    A simple mathematical equation relates the input signal,
    reference voltage, and integration time:
    TC7136/A PIN DESCRIPTION (Cont.)
    Pin No.
    40-Pin PDIP
    Normal
    (Reverse)
    Name
    Description
    33
    (8)
    C
    REF
    See pin 34.
    34
    (7)
    C
    +
    REF
    A 0.1
    F capacitor is used in most applications. If a large common-mode
    voltage exists (for example, the V
    IN pin is not at analog common), and a 200
    mV scale is used, a 1
    F capacitor is recommended and will hold the roll-over
    error to 0.5 count.
    35
    (6)
    V
    REF
    See pin 36.
    (5)
    V
    +
    REF
    The analog input required to generate a full-scale output (1999 counts). Place
    100 mV between pins 35 and 36 for 199.9 mV full scale. Place 1V between
    pins 35 and 36 for 2V full scale. See paragraph on Reference Voltage.
    36
    (4)
    TEST
    Lamp test. When pulled HIGH (to V+) all segments will be turned ON and the
    display should read –1888. It may also be used as a negative supply for exter-
    nally-generated decimal points. See paragraph under Test for additional informa-
    tion.
    37
    (3)
    OSC3
    See pin 40.
    38
    (2)
    OSC2
    See pin 40.
    39
    (1)
    OSC1
    Pins 40, 39 and 38 make up the oscillator section. For a 48kHz clock (3 readings per
    second) connect pin 40 to the junction of a 180 k
    resistor and a 50pF capacitor. The
    180k
    resistor is tied to pin 39 and the 50pF capacitor is tied to pin 38.
    For a constant VIN:
    VIN = VR
    .
    1VR tRI
    RC
    VIN(t) dt =
    ,
    tSI
    where:
    VR = Reference voltage
    tSI = Signal integration time (fixed)
    tRI = Reference voltage integration time (variable).
    Figure 1. Basic Dual-Slope Converter
    +
    REF
    VOLTAGE
    ANALOG
    INPUT
    SIGNAL
    +
    DISPLAY
    SWITCH
    DRIVER
    CONTROL
    LOGIC
    INTEGRATOR
    OUTPUT
    CLOCK
    COUNTER
    POLARITY CONTROL
    PHASE
    CONTROL
    VIN
    VFULL SCALE
    1.2 VFULL SCALE
    VARIABLE
    REFERENCE
    INTEGRATE
    TIME
    FIXED
    SIGNAL
    INTEGRATE
    TIME
    INTEGRATOR
    CINT
    COMPARATOR
    tRI
    tSI
    [ ]
    0
    相關PDF資料
    PDF描述
    TC7136RCLW 1-CH DUAL-SLOPE ADC, PQCC44
    TC74HC4051AFN 8-CHANNEL, SGL ENDED MULTIPLEXER, PDSO16
    TC74HC4052AFN 4-CHANNEL, DIFFERENTIAL MULTIPLEXER, PDSO16
    TC74LVX4052FT 4-CHANNEL, DIFFERENTIAL MULTIPLEXER, PDSO16
    TC7USB221FT DUAL 1-CHANNEL, SGL POLE DOUBLE THROW SWITCH, PDSO14
    相關代理商/技術參數
    參數描述
    TC7136ARCPL 功能描述:LCD 驅動器 Low Power RoHS:否 制造商:Maxim Integrated 數位數量:4.5 片段數量:30 最大時鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
    TC7136CKW 功能描述:LCD 驅動器 Low Power RoHS:否 制造商:Maxim Integrated 數位數量:4.5 片段數量:30 最大時鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
    TC7136CKW713 功能描述:LCD 驅動器 Low Power RoHS:否 制造商:Maxim Integrated 數位數量:4.5 片段數量:30 最大時鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
    TC7136CLW 功能描述:LCD 驅動器 Low Power RoHS:否 制造商:Maxim Integrated 數位數量:4.5 片段數量:30 最大時鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
    TC7136CLW713 功能描述:LCD 驅動器 Low Power RoHS:否 制造商:Maxim Integrated 數位數量:4.5 片段數量:30 最大時鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube