Analog to Digital Analog to Digital Converter Converter

David WallaceDavid Wallace

English 314English 314

What is a Analog to What is a Analog to Digital Converter?Digital Converter?

OverviewOverview

Electricity ReviewElectricity Review

Circuitry basicsCircuitry basics

ConceptsConcepts

DesignDesign

DemonstrationDemonstration

ApplicationsApplications

ConclusionConclusion

Electricity ReviewElectricity Review

Voltage is the measure of potential energy Voltage is the measure of potential energy between separated positively and between separated positively and negatively charged particlesnegatively charged particles

Voltage is measured in VoltsVoltage is measured in Volts

Current is the flow of positively charged Current is the flow of positively charged particles into negatively charged particles particles into negatively charged particles by means of wire or circuitryby means of wire or circuitry

Current is measured in AmperesCurrent is measured in Amperes

V=iRV=iR

Circuitry UsedCircuitry Used

Socket boardSocket board

Resistor Resistor

Operational AmplifierOperational Amplifier

LEDLED

Power SupplyPower Supply

Socket BoardSocket Board

Also known as a breadboardAlso known as a breadboard

Used as a temporary circuit boardUsed as a temporary circuit board

ResistorResistorThen resistor is the most basic of all electrical Then resistor is the most basic of all electrical circuitrycircuitry

The resistor impedes the flow of currentThe resistor impedes the flow of current

One of the most widely used circuit elementsOne of the most widely used circuit elements

Operational AmplifierOperational Amplifier

Produces an Produces an amplified voltageamplified voltageCompares the two Compares the two inputs and creates a inputs and creates a output voltage based output voltage based on the input on the input differencedifferenceCan be used to make Can be used to make very complex circuitsvery complex circuitsCan be used to make Can be used to make comparators comparators

LEDLED

LLight ight EEmitting mitting DDiodeiode

When there is current When there is current flowing through the flowing through the light it turns on, light it turns on, otherwise it is offotherwise it is off

Diodes only allow Diodes only allow current to flow one current to flow one directiondirection

Power SupplyPower Supply

This circuit requires This circuit requires DC voltageDC voltage

DC stands for direct DC stands for direct currentcurrent

DC power supplies DC power supplies keep the voltage at a keep the voltage at a constant levelconstant level

Design ConceptsDesign Concepts

Breadboard usageBreadboard usage

Resistance laddersResistance ladders

ComparatorsComparators

LED ProtectionLED Protection

How to use a breadboardHow to use a breadboardRecall the lines Recall the lines connecting the dots in connecting the dots in the middle of the the middle of the boardboard

Many pieces of Many pieces of circuitry can be circuitry can be placed on one line to placed on one line to make the necessary make the necessary connects for the connects for the circuitcircuit

Resistance LaddersResistance LaddersUsually the resistors Usually the resistors used are all the same used are all the same size or their size will size or their size will increase evenly with increase evenly with each resistoreach resistorIn this circuit the In this circuit the resistors will all be resistors will all be identical within 5% identical within 5% accuracyaccuracyVoltage will drop in Voltage will drop in even increments even increments across each resistoracross each resistor

ComparatorsComparators

This is the most simple way to use an op-ampThis is the most simple way to use an op-ampIf the voltage on the positive input is greater than If the voltage on the positive input is greater than the voltage on the negative the output will be the voltage on the negative the output will be equal to Vequal to VCCCC

Otherwise the voltage on the output is equal to Otherwise the voltage on the output is equal to VVEE EE or ground in our circuitor ground in our circuit

LED ProtectionLED Protection

To protect the LED from being damaged, To protect the LED from being damaged, resistors are usedresistors are used

A resistor is placed in between the LED A resistor is placed in between the LED and ground to limit the amount of current and ground to limit the amount of current that flows trough the lightthat flows trough the light

Circuit DesignCircuit Design

Circuit EquipmentCircuit Equipment

1 - Small breadboard1 - Small breadboard

6 - 1000 Ohm resistors (4-Band (brown – black – 6 - 1000 Ohm resistors (4-Band (brown – black – orange – gold)) orange – gold))

1 - Texas Instruments 324 series op-amps 1 - Texas Instruments 324 series op-amps (LM324N)(LM324N)

4 - LED’s 4 - LED’s

3 - Voltage sources (1-5V DC, 2-Adjustable DC)3 - Voltage sources (1-5V DC, 2-Adjustable DC)

9 - Pieces of wire9 - Pieces of wire

4 – Wires that can connect your power source to 4 – Wires that can connect your power source to your socket boardyour socket board

Circuit UsesCircuit Uses

Visually displaying a comparison of one Visually displaying a comparison of one voltage to anothervoltage to another

Widely used in measuring devicesWidely used in measuring devices

Real Life ApplicationReal Life Application

One of the most common used for a circuit One of the most common used for a circuit like this is in sound equipmentlike this is in sound equipment

An ADC is usually used to represent An ADC is usually used to represent volume levelsvolume levels

ConclusionConclusion

The ADC is a relatively easy circuit to The ADC is a relatively easy circuit to create and implementcreate and implement

Very few parts are usedVery few parts are used

Concepts are easy to understandConcepts are easy to understand

ExpandableExpandable

VersatileVersatile

Questions?Questions?