Analog to Digital Converter David Wallace English 314

What is a Analog to Digital Converter?

Overview Electricity Review Circuitry basics ConceptsDesignDemonstrationApplicationsConclusion

Electricity Review Voltage is the measure of potential energy between separated positively and negatively charged particles Voltage is measured in Volts Current is the flow of positively charged particles into negatively charged particles by means of wire or circuitry Current is measured in Amperes V=iR

Circuitry Used Socket board Resistor Operational Amplifier LED Power Supply

Socket Board Also known as a breadboard Used as a temporary circuit board

Resistor Then resistor is the most basic of all electrical circuitry The resistor impedes the flow of current One of the most widely used circuit elements

Operational Amplifier Produces an amplified voltage Compares the two inputs and creates a output voltage based on the input difference Can be used to make very complex circuits Can be used to make comparators

LED Light Emitting Diode When there is current flowing through the light it turns on, otherwise it is off Diodes only allow current to flow one direction

Power Supply This circuit requires DC voltage DC stands for direct current DC power supplies keep the voltage at a constant level

Design Concepts Breadboard usage Resistance ladders Comparators LED Protection

How to use a breadboard Recall the lines connecting the dots in the middle of the board Many pieces of circuitry can be placed on one line to make the necessary connects for the circuit

Resistance Ladders Usually the resistors used are all the same size or their size will increase evenly with each resistor In this circuit the resistors will all be identical within 5% accuracy Voltage will drop in even increments across each resistor

Comparators This is the most simple way to use an op-amp If the voltage on the positive input is greater than the voltage on the negative the output will be equal to V CC Otherwise the voltage on the output is equal to V EE or ground in our circuit

LED Protection To protect the LED from being damaged, resistors are used A resistor is placed in between the LED and ground to limit the amount of current that flows trough the light

Circuit Design

Circuit Equipment 1 - Small breadboard Ohm resistors (4-Band (brown – black – orange – gold)) 1 - Texas Instruments 324 series op-amps (LM324N) 4 - LED’s 3 - Voltage sources (1-5V DC, 2-Adjustable DC) 9 - Pieces of wire 4 – Wires that can connect your power source to your socket board

Circuit Uses Visually displaying a comparison of one voltage to another Widely used in measuring devices

Real Life Application One of the most common used for a circuit like this is in sound equipment An ADC is usually used to represent volume levels

Conclusion The ADC is a relatively easy circuit to create and implement Very few parts are used Concepts are easy to understand ExpandableVersatile

Questions?