9/4/2015Ronel Vidal, ECE1 ELECTRONICS ENGINEERING 1 INTRODUCTION

9/4/2015Ronel Vidal, ECE2 the science dealing with the development and application of devices and systems involving the flow of electrons or other carriers of electric charge, in a vacuum, in gaseous media, in plasma, in semiconductors, in solid-state and/or in similar devices, including, but not limited to, applications involving optical, electromagnetic and other energy forms when transduced or converted into electronic signals. ELECTRONICS

9/4/2015Ronel Vidal, ECE3 APPLICATIONS OF ELECTRONICS COMMUNICATIONS ELECTRONICS ELECTRIC POWER DIGITAL ELECTRONICS AUTOMOTIVE ELECTRONICS INDUSTRIAL ELECTRONICS MEDICAL ELECTRONICS CONSUMER ELECTRONICS

9/4/2015Ronel Vidal, ECE4 2 TYPES OF ELECTRONIC SIGNAL ANALOG – ELECTRONIC SIGNALS THAT THE AMPLITUDE CHANGES CONTINUOUSLY WITH RESPECT TO TIME WITH NO BREAKS OR DISCONTINUITIES. DIGITAL – ELECTRONIC SIGNALS THAT ARE DESCRIBE AS DISCRETE; THEIR AMPLITUDE MAINTAINS A CONSTANT LEVEL FOR A PRESCRIBED PERIOD OF TIME THEN IT CHANGES TO ANOTHER LEVEL.

9/4/2015Ronel Vidal, ECE5 TWO TYPES OF ELECTRONIC CIRCUIT DISCRETE CIRCUIT – Electronic circuit that is composed of individual circuit components. INTEGRATED CIRCUIT (IC) – Electronic circuit with thousands of circuit components in a single package.

9/4/2015Ronel Vidal, ECE6 CLASSIFICATIONS OF ELECTRONIC COMPONENTS ACCORDING TO FUNCTION ACTIVE SEMICONDUCTORS ELECTRON TUBES VDD (Visual Display Devices) PASSIVE RESISTOR, CAPACITOR & INDUCTOR

9/4/2015Ronel Vidal, ECE7 ELECTRONIC COMPONENTS SEMICONDUCTORS DIODE, TRANSISTOR, ICs, etc. RESISTORS CAPACITORS INDUCTOR/ COIL ELECTRON TUBES VACUUM TUBES, PICTURE TUBES, CRT (Cathode Ray Tube) VISUAL DISPLAY DEVICES LCD (Liquid Crystal Display) LED ( Light Emitting Diode)

9/4/2015Ronel Vidal, ECE8 ELECTRONIC CIRCUIT REPRESENTATION (ELECTRONIC CIRCUIT DIAGRAM) Block Diagram Circuit Diagram (Schematic) Pictorial Diagram

9/4/2015Ronel Vidal, ECE9 Block Diagrams Block diagrams are used to understand (and design) complete circuits by breaking them down into smaller sections or blocks. Each block performs a particular function and the block diagram shows how they are connected together. No attempt is made to show the components used within a block, only the inputs and outputs are shown. This way of looking at circuits is called the systems approach. Power supply (or battery) connections are usually not shown on block diagrams.

9/4/2015Ronel Vidal, ECE10 Audio Amplifier System The power supply (not shown) is connected to the pre-amplifier and power amplifier blocks. Microphone - a transducer which converts sound to voltage. Pre-Amplifier - amplifies the small audio signal (voltage) from the microphone. Tone and Volume Controls - adjust the nature of the audio signal. The tone control adjusts the balance of high and low frequencies. The volume control adjusts the strength of the signal. Power Amplifier - increases the strength (power) of the audio signal. Loudspeaker - a transducer which converts the audio signal to sound.

9/4/2015Ronel Vidal, ECE11 Radio Receiver System The power supply (not shown) is connected to the audio amplifier block. Aerial - picks up radio signals from many stations. Tuner - selects the signal from just one radio station. Detector - extracts the audio signal carried by the radio signal. Audio Amplifier - increases the strength (power) of the audio signal. Loudspeaker - a transducer which converts the audio signal to sound.

9/4/2015Ronel Vidal, ECE12 Regulated Power Supply System Transformer - steps down 230V AC mains to low voltage AC. Rectifier - converts AC to DC, but the DC output is varying. Smoothing - smooths the DC from varying greatly to a small ripple. Regulator - eliminates ripple by setting DC output to a fixed voltage.

9/4/2015Ronel Vidal, ECE13 Feedback Control System

9/4/2015Ronel Vidal, ECE14 Feedback Control System The power supply (not shown) is connected to the control circuit block. Sensor - a transducer which converts the state of the controlled quantity to an electrical signal. Selector (control input) - selects the desired state of the output. Usually it is a variable resistor. Control Circuit - compares the desired state (control input) with the actual state (sensor) of the controlled quantity and sends an appropriate signal to the output transducer. Output Transducer - converts the electrical signal to the controlled quantity.

9/4/2015Ronel Vidal, ECE15 Feedback Control System Controlled Quantity - usually not an electrical quantity, e.g. motor speed. Feedback Path - usually not electrical, the Sensor detects the state of the controlled quantity.

9/4/2015Ronel Vidal, ECE16 Circuit Diagram Circuit diagrams show how electronic components are connected together. Each component is represented by a symbol.

9/4/2015Ronel Vidal, ECE17 Wires and Connections componentcircuit symbolfunction Wire ________ To pass current very easily from one part of a circuit to another. Wires joinedA 'blob' should be drawn where wires are connected (joined), but it is sometimes omitted. Wires connected at 'crossroads' should be staggered slightly to form two T-junctions.

9/4/2015Ronel Vidal, ECE18 Wires and Connections componentcircuit symbolfunction Wires not joined In complex diagrams it is often necessary to draw wires crossing even though they are not connected. The 'hump' symbol is preferable because the simple crossing on the left may be misread as a join where you have forgotten to add.

9/4/2015Ronel Vidal, ECE19 Wires and Connections component circuit symbolfunction CellSupplies electrical energy. A single cell is often wrongly called a battery, but strictly a battery is two or more cells joined together. BatterySupplies electrical energy. A battery is more than one cell.

9/4/2015Ronel Vidal, ECE20 Wires and Connections component circuit symbolfunction DC supply Supplies electrical energy. DC = Direct Current, always flowing in one direction. AC supply Supplies electrical energy. AC = Alternating Current, continually changing direction.

9/4/2015Ronel Vidal, ECE21 Power Supplies component circuit symbolfunction fuseA safety device which will 'blow' (melt) if the current flowing through it exceeds a specified value. transformerTwo coils of wire linked by an iron core. Transformers are used to step up (increase) and step down (decrease) AC voltages. Energy is transferred between the coils by the magnetic field in the core. There is no electrical connection between the coils.

9/4/2015Ronel Vidal, ECE22 Power Supplies component circuit symbol function Earth (ground) A connection to earth. For many electronic circuits this is the 0V (zero volts) of the power supply, but for mains electricity and some radio circuits it really means the earth. It is also known as ground.

9/4/2015Ronel Vidal, ECE23 Output Devices: Lamps, Heater, Motor, etc. ComponentCircuit SymbolFunction Lamp (lighting) A transducer which converts electrical energy to light. This symbol is used for a lamp providing illumination, for example a car headlamp or torch bulb. Lamp (indicator) A transducer which converts electrical energy to light. This symbol is used for a lamp which is an indicator, for example a warning light on a car dashboard.

9/4/2015Ronel Vidal, ECE24 Output Devices: Lamps, Heater, Motor, etc. ComponentCircuit SymbolFunction HeaterA transducer which converts electrical energy to heat. MotorA transducer which converts electrical energy to kinetic energy (motion). BellA transducer which converts electrical energy to sound.

9/4/2015Ronel Vidal, ECE25 Output Devices: Lamps, Heater, Motor, etc. Component Circuit SymbolFunction BuzzerA transducer which converts electrical energy to sound. Inductor (Coil, Solenoid) A coil of wire which creates a magnetic field when current passes through it. It may have an iron core inside the coil. It can be used as a transducer converting electrical energy to mechanical energy by pulling on something.

9/4/2015Ronel Vidal, ECE26 Switches ComponentCircuit SymbolFunction Push Switch a. push-to- make A push switch allows current to flow only when the button is pressed. This is the switch used to operate a doorbell. b. push-to- break This type of push switch is normally closed (on), it is open (off) only when the button is pressed.

9/4/2015Ronel Vidal, ECE27 Switches Component Circuit SymbolFunction On-Off Switch (SPST) SPST = Single Pole, Single Throw. An on-off switch allows current to flow only when it is in the closed (on) position. 2-way Switch (SPDT) SPDT = Single Pole, Double Throw. A 2-way changeover switch directs the flow of current to one of two routes according to its position. Some SPDT switches have a central off position and are described as 'on-off-on'.

9/4/2015Ronel Vidal, ECE28 Switches ComponentCircuit SymbolFunction Dual On-Off Switch (DPST) DPST = Double Pole, Single Throw. A dual on-off switch which is often used to switch mains electricity because it can isolate both the live and neutral connections. Reversing Switch (DPDT) DPDT = Double Pole, Double Throw. This switch can be wired up as a reversing switch for a motor. Some DPDT switches have a central off position.

9/4/2015Ronel Vidal, ECE29 Switches ComponentCircuit SymbolFunction RelayAn electrically operated switch, for example a 9V battery circuit connected to the coil can switch a 230V AC mains circuit. NO = Normally Open, COM = Common, NC = Normally Closed.

9/4/2015Ronel Vidal, ECE30 Circuit Diagram and Component Layouts Circuit diagrams show the connections as clearly as possible with all wires drawn neatly as straight lines. The actual layout of the components is usually quite different from the circuit diagram. A circuit diagram is useful when testing a circuit and for understanding how it works.

9/4/2015Ronel Vidal, ECE31

9/4/2015Ronel Vidal, ECE32 Drawing Circuit Diagrams not difficult but it takes a little practice to draw neat, clear diagrams a useful skill for science as well as for electronics You will certainly need to draw circuit diagrams if you design your own circuits

9/4/2015Ronel Vidal, ECE33 Drawing Circuit Diagrams Follow these tips for best results: Make sure you use the correct symbol for each component. Draw connecting wires as straight lines (use a ruler). Put a 'blob' ( ) at each junction between wires. Label components such as resistors and capacitors with their values. The positive (+) supply should be at the top and the negative (-) supply at the bottom. The negative supply is usually labeled 0V, zero volts.

9/4/2015Ronel Vidal, ECE34 Drawing Complex Circuit Diagrams Try to arrange the diagram so that signals flow from left to right: inputs and controls should be on the left, outputs on the right. You may omit the battery or power supply symbols, but you must include (and label) the supply lines at the top and bottom.

9/4/2015Ronel Vidal, ECE35

9/4/2015Ronel Vidal, ECE36 End of Lesson 1