ANALOG TO DIGITAL AND DIGITAL TO ANALOG CONVERTER

ANALOG TO DIGITAL AND DIGITAL TO ANALOG CONVERTER

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  A/D AND D/ACONVERTER BY SRIPATI MAHAPATRA
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  AMPLIFIER An electronic amplifieris a device for increasing the power of a signal. It does this by taking energy from a power supply and controlling the output to match the input signal shape but with a larger amplitude. In this sense, an amplifier may be considered as modulating the output of the power supply TYPES OF AMPLIFIER Inverting Amplifier Non-Inverting Amplifier
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  OP-AMP (Operational Amplifier) AnOperational Amplifier, or Op Amp, is a dual-input, single-output amplifier that exhibits a high open-loop gain, high input resistances, and a low output resistance. One of the inputs of an operational amplifier amp is non-inverting while the other is inverting. The output Vout of an operational amplifier without feedback (also known as open-loop) is given by the formula: Vout = A(Vp-Vn) where A is the open-loop gain of the op amp, Vp is the voltage at the non-inverting input, and Vn is the voltage at the inverting input.
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  INVERTING AMPLIFIER Amplifier whoseoutput polarity is reversed as compared to its input; such an amplifier obtains its negative feedback by a connection from output to input, and with high gain is widely used as an operational amplifier. GAIN (Av) = -Rf/R1
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  NON-INVERTING AMPLIFIER An operationalamplifier in which the input signal is applied to the ungrounded positive input terminal to give a gain greater than unity and make the output voltage change in phase with the input voltage. GAIN (Av) = 1+RF/R2
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  D/A CONVERTER Weighted-register D/Aconverter R-2R ladder D/A converter Weighted-register D/A converter The OP-Amp adder circuit is used to build a Weighted-register D/A converter by selecting input register that are weighted in binary progression.
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  Output Voltage (V0)= -RFV1/R1-RFV2/R2-RFV3/R3 V0 = -(RFV1/R1+RFV2/R2+RFV3/R3) R=2R ladder D/A Converter An R-2R Ladder is a simple and inexpensive way to perform digital- to-analog conversion, using repetitive arrangements of precision resistor networks in a ladder-like configuration. As its name implies, the R-2R network consists of resistors with only two values, R and 2R (10K and 20K, respectively, in the circuit shown). The input SN to bit N is '1' if it is connected to a voltage VR and '0' if it is grounded.
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  Analog to DigitalConverter An analog-to-digital converter (abbreviated ADC, A/D or A to D) is a device that converts a continuous quantity to a discrete digital number. Or A device that converts continuously varying analog signals from instruments and sensors that monitor conditions, such as sound, movement and temperature into binary code for the computer. The A/D converter may be contained on a single chip or can be one circuit within a chip.
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  TYPES Counting A/D Converter Dualslope A/D converter Parallel A/D Converter A/D Converter using voltage for frequency conversion A/D Converter using voltage to time conversion