Electronic workshop Lecture-1 Power Supplies & Measuring Instruments Dr. Imtiaz Hussain email: imtiaz.hussain@faculty.muet.edu.pk URL :http://imtiazhussainkalwar.weebly.com/

Outline Course Objectives Course Outline Recommended Books Marks Distribution Workshop#1 Introduction to Electronics Electronics vs. Electrical Electricity A.C vs. D.C Power Supplies Measuring Instruments

Course Objectives Hands on experience with the use of laboratory equipment. Recognize discrete components and ICs. Read and understand the data sheets. Working experience with prototype board and solder and desolder the discrete components on a project board. Assemble simple circuits over a PCB.

Operation of Electronic Equipment Course Outline Operation of Electronic Equipment Voltmeters Ohmmeters Ammeters Power supplies function generator Oscilloscope Passive Components Resistor Capacitor Inductor Active Components Diode Types Datasheets Transistor Circuit Assembly Bread Board Vero Board Soldering De-soldering PCB Layout

Recommended Books Dr. B.S. Chowdhry & Ahsan A. Ursani, “The First Practical Book on Electronic Workshop”, published by Mehran Infotech Consultants, Hyderabad, Paul Horowitz & Ian Robinson, "Laboratory Manual for Art of Electronics”, Cambridge University Press. Bernard Grobe, "Basic Electronics". Paul B. Znbar, Albert P. Malvino, "Basic Electronics Text Lab Manual", McGraw Hill.

Prerequisites Physics (Intermediate Level)

Marks Distribution Theory Practical Total Marks = 00 Total Marks = 50 Sessional Marks = 20 Attendance = 05 marks Case Study/Project/ Test = 15 marks Midterm Exam Final Exam Marks = 30

What is Electronics? General Definition Modern Definition The science dealing with the development and application of devices and systems involving the flow of electrons in a vacuum, in gaseous media, and in semiconductors. Modern Definition The science dealing with the development and application of devices and systems involving the flow of electrons in semiconductors.

Electronics vs. Electrical According to Wikipedia Electrical Engineering is a field of engineering that generally deals with the study and application of electricity, electronics, and electromagnetism.   Electronic Engineering, is an engineering discipline where non-linear and active electrical components such as electron tubes, and semiconductor devices, especially transistors, diodes and integrated circuits, are utilized to design electronic circuits, devices and systems.

Electronics vs. Electrical Main Difference Electrical Engineering Study and utilization/ Application of flow of electrons Electronic Engineering Study and utilization/ Application of flow of charges (Electrons or holes)

Electricity Two forms of electricity Static Electricity is an electrical charge at rest Produced by either magnetism, chemicals, light, heat, or pressure

Produced Electricity Magnetism – Electric Generators Chemical – Battery, Fuel Cells Light – Photocell (solar cell) Heat – Thermocouple (nuclear power) Pressure - Crystals

Alternating Current If the high & low voltage terminals switch locations periodically, the current will flow “back and forth” in the circuit. This is called alternating current (AC).

Alternating Current It is the form that comes in our house mains. It has a magnitude of 220V and a frequency of 50Hz.

Direct Current If the voltage is maintained between two points in a circuit, charge will flow in one direction - from high to low potential. This is called direct current (DC)

AC vs. DC Most of the home appliances run on D.C. Each home appliance is equipped with its own power supply. Why we are supplied AC when most of the appliances run on D.C?

Symbols of Power Sources

Power Supply A power supply is a device that supplies electric power to an electrical load. 

Type (Tick the Relevant Choice) Task#1 Your first task is to list all the power supplies available in this lab and fill out the following table.   S. N.o Model Type (Tick the Relevant Choice) Range AC DC Voltage Current 1.   2. 3. 4. 5.

Measuring Instruments A measuring instrument is a device for measuring a physical quantity. Instruments for measuring electrical quantitates Voltmeter (for measuring Voltage) Ammeter (for measuring current) Ohmmeter (for measuring resistance) Multimeter (for measuring all three quantities)

Voltmeter AC and DC Voltmeters

Voltmeter Voltmeters have high impedance and hence are connected in parallel across the points between which potential difference is to be measured. Voltmeter

Ammeter AC and DC ammeter

Ammeter Ammeters, on the other hand exhibit a very small resistance, and hence are connected in series, Ammeter

Ohmmeter

Ohmmeter

Multimeter Analog vs Digital

Digital Multimeter A multimeter is has three parts: Display Selection Knob Ports

Digital Multimeter Two probes are plugged into two of the ports on the front of the unit.  COM stands for common and is almost always connected to Ground or ‘-’ of a circuit. The COM probe is conventionally black but there is no difference between the red probe and black probe other than color. 

Digital Multimeter 10A is the special port used when measuring large currents (greater than 200mA).  mAVΩ is the port that the red probe is conventionally plugged in to. This port allows the measurement of current (up to 200mA), voltage (V), and resistance (Ω).

Task#2 Your second task is to list all the measuring instruments available in this lab and fill out the following table.   S. N.o Model Type (Analog/ Digital) Measured Quantity V AC I AC V DC I DC R 1.   2. 3. 4. 5.

Measuring voltage Using Digital Multimeter To start, let’s measure voltage on a AA battery: Plug the black probe into COM and the red probe into mAVΩ.  Set the multimeter to “2V” in the DC (direct current) range Connect the black probe to the battery’s ground or ‘-’ and the red probe to power or ‘+’

Measuring resistance Using Digital Multimeter Pick out a random resistor and set the multimeter to the 20kΩ setting

Measuring Current Using Digital Multimeter Reading current is one of the trickiest and most insightful readings in our world of electronics. It’s tricky because you have to measure current in series. 

Continuity Testing Using Digital Multimeter Continuity testing is the act of testing the resistance between two points. If there is very low resistance (less than a few Ωs), the two points are connected electrically and a tone is emitted. If there is more than a few Ωs of resistance, than the circuit is open and no tone is emitted. This test helps insure that connections are made correctly between two points. This test also helps us detect if two points are connected that should not be.

Continuity Testing Using Digital Multimeter Set the multimeter to ‘Continuity’ mode. It may vary among DMMs, but look for a diode symbol with propagation waves around it (like sound coming from a speaker).

Task#3 Take a digital multimeter and fill in the following table for any of the Voltage Sources S N.o Selected Voltage (a) Measured Voltage (b) Percent Error 𝒂−𝒃 𝒂 ×𝟏𝟎𝟎 1.   2. 3. 4.

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