Republic of the Philippines
Department of Education
Region V
SCHOOLS DIVISION OF SORSOGON
LEARNING ACTIVITY SHEET
Quarter - 1
TECHNOLOGY AND LIVELIHOOD EDUCATION – Grade 10
Electronic Product Assembly and Servicing
Student Name: ______________________ Grade & Section: ______________
Teacher: ___________________________ Date Submitted: ______________
I. Introductory Concept
In this lesson, you will learn about the Basic parts, the different types, as well as how the
Converter Power Supply works in a circuit.
II. Learning Competencies: Install consumer electronic products and systems
Code: TLE_IAEPAS9-12SCEP-DEARE-IVb-f-43
Sub Topic: Obtain materials necessary to complete the work are obtained in
accordance with job requirements
OBJECTIVE/S
1. Define Converter Power Supply
2. Enumerate the Parts and Function of CPS
3. Draw the Schematic Diagram of CPS
III. Activities
A. Lesson Information
Converter Power Supply Operation
A Converter power supply is an electronic device that supplies electrical energy to an electrical load
(Appliances, Gadgets) .In a day to day life thousands of the Electronic devices are used like TV, radio, mobile,
laptop etc. Most of these electronic devices require Direct Current Supply or DC but in our houses and industries
Alternating Current Supply or AC is available. Now, the question is “how would we convert AC Supply to a DC
Supply? The answer is Rectifier. The primary function of a Rectifier is to converts an AC Voltage to DC Voltage.
A power supply is the heart of all electronic equipment. It converts AC input power from grid line to DC
output voltage (AC-DC). It supplies the desired voltage and current in a circuit. Without these, all electronic
equipment will not function at all.
A basic power supply consists of three basic stages: the power transformer stage, rectifier stage, and filter
stage. If there is a need to regulate the output voltage, a regulator circuit is added.
Parts of a Converter Power Supply
1. Plug and wire- The part of the circuit where the current or the electricity flows, it is made up of conducting
materials “conductor”. These are the materials that conduct electricity and allow electricity to pass through.
2. Fuse- The purpose of a fuse is to protect the wiring and the equipment usually a thin piece of wire that will
melt and break the circuit if too large a current flows through it.
3. Step-down Transformer- An electronic component that is used to step-down/ converts higher input or
power coming from the power lines to a smaller output. (Ex: 220VAC to 12VAC)
4. Rectifier Diode- Converts Alternating Current to Direct Current.
5. Regulator – Designed to provide a very steady and well regulated DC output. The output level is
maintained regardless of the variation of the input voltage. It is always ideal to have a steady output
voltage so that the load will operate properly.
6. Filter Capacitor- The function is to change the pulsating DC produced by the rectifier to a smooth DC.
Usually an Electrolytic Capacitor is used
TLE-EPAS_Grade10_Q1_LAS3
Types of Rectifier Circuit
There are two types of rectifier, Half-wave Rectifier and the Full-wave
Rectifier. Under a Full-wave rectifier, there are two types, the Center-tapped and the Bridge Rectifier.
1. Half-wave Rectifier Circuit
One rectifier diode D1 and one load resistor RL are needed to conduct one alteration in every
cycle of small AC input.
Note: Compare the difference of the three circuits in your lecture:
a. Half-wave
b. Full-wave
Center-tapped
Bridge
Schematic Diagram of a Half-Wave Rectifier
2. Full-Wave Center-Tapped Rectifier Circuit
This type of circuit requires a center-tapped transformer, two rectifier diodes, and a load resistor (RL).
Each of the diode supplies one-half the DC load current.
Schematic
Diagram of a Full-Wave
Center- Tapped Rectifier
circuit
The full-wave bridge
type rectifier circuit uses four
rectifier diodes D1, D2,
D3, D4 and a load resistor
(RL). A center-tapped
transformer is not necessary
in this circuit. This
circuit can deliver a higher
current range to the
load because all of the cycles are consumed by the four diodes. The operation of this rectifier circuit is different
from the Half-wave and Full-wave center-tapped. The conduction of AC voltage starts from Line-A going to Line-B
Conduction of Diode in Full-Wave Bridge Type Rectifier Circuit
First Conduction
The negative half-cycle will be conducted to the cathode of diode D1, and then thru the RL it will conduct to
the cathode of diode D4 goes to LineB. In this case D1 and D4 are conducting.
First Conduction in a Full-wave Bridge Type Rectifier Circuit
Second Conduction
The positive half-
cycle will be conducted to
the anode of diode D2 and
then thru the RL, it will
conduct to the anode of
diode D3 goes to Line-B. In
this case D2 and D3 are
conducting.
Second Conduction in a Full
Wave Bridge Type Rectifier
Circuit
TLE-EPAS_Grade10_Q1_LAS3
Filter Stage
This stage of the power supply smoothen the pulsating DC output voltage of rectifier circuit by reducing the
amount of ripple voltage. It also provides the charge voltage for the load while the rectifier diode is not conducting
Basic Methods of Filtering
1. Simple Capacitor in Parallel
You can connect as many electrolytic capacitors in parallel as you want in order to increase the amount of
capacitance causing good filtering effects to DC output. This is used for high current applications. The only
disadvantage is that it will occupy a bigger space.
2. Filter with RC Circuit
This circuit is actually a resistor in series with the positive line together with two bypass capacitors C1 and
C2. It is good in lowering the DC voltage output.
B. TASK 1: Identification
DIRECTIONS: DIRECTION: Answer the following questions and write your answers in the Answer
Sheet.
1. How many stages do basic power supplies have?
2. What component do we need to use in a simple basic filtering stage?
3. What stage of the power supply reduces the high AC input voltage to a lower AC output voltage?
4. What stage of the power supply converts small AC voltage to pulsating DC voltage?
5. How many diodes do full-wave center-tapped power supplies have?
C. TASK 2: Enumeration
DIRECTIONS: DIRECTION: Enumerate the parts of the Power Supply based on their uses and
functions. Write your answers in the Answer Sheet.
1. The function is to change the pulsating DC to a smooth DC. Usually an Electrolytic Capacitor is used
2. Is to protect the Circuit if too large amount of a current flows through it.
3. Converts Alternating Current to Direct Current
4. An electronic component that is used to step-down/ converts higher input or power coming from the power
lines to a smaller output. (Ex: 220VAC to 12VAC)
5. The part of the circuit where the current or the electricity flows, it is made up of conducting materials
“conductor”. These are the materials that conduct electricity and allow electricity to pass through.
6. Designed to provide a very steady and well regulated DC output. The output level is maintained regardless
of the variation of the input voltage. It is always ideal to have a steady output voltage so that the load will
operate properly.
D. PERFORMANCE ASSESSMENT
Direction: Draw the schematic diagram of bridge type rectifier circuit, write/draw your answer in the answer
sheet:
TLE-EPAS_Grade10_Q1_LAS3
PERFORMANCE CRITERIA CHECKLIST:
CRITERIA
Number of Tools Classified Score
1 Complete components/ correct connection/ with label/ correct symbols 5
2 Complete components/ correct connection/ no label/ correct symbols 4
3 Complete components/ correct connection/ no label/incorrect symbol 3
4 Complete components/ incorrect connection/ no label/incorrect symbols 2
5 Complete components/ incorrect connection/ no label/incorrect symbols 1
SCORING RUBRICS:
SCORE INTERPRETATION OF SCORE POINT
5 Excellent 10
4 Very Good 9
3 Good 7
2 Fair 5
1- Below Poor 3
IV. EVALUATION
MULTIPLE CHOICE: Read the questions carefully and choose the letter of the correct answer. Write your
answer on the Answer Sheet.
1. In a bridge-type rectifier circuit, there are four terminal joints.
Select the one that could give a DC+ output.
a. Anode-Cathode c. Two Anode
b. Infinite d. Two Cathode
2. In a bridge-type rectifier circuit, there are four terminal joints.
Select the one that is connected to one of the AC output of transformer.
a. Anode-Cathode c. Two Anode
b. None d. Two Cathode
3. The positive electrode of a device. It is the “P” material of a diode.
a. Anode c. Cathode
b. Bridge-type Rectifier d. Full wave rectifier circuit
4. It refers to a circuit using four diodes that provides full wave rectification.
a. Anode c. Cathode
b. Bridge-type Rectifier d. Full-wave rectifier circuit
5. How many diode/s are there in the half-wave rectifier?
a. One b. two c. three d. four
V. Answer Key
TASK 1: TASK 2: EVALUATION:
1. THREE 1. FILTER 1. C
2. CAPACITOR 2. FUSE 2. A
3. TRANSFORMER STAGE 3. RECTIFIER 3. A
4. RECTIFIER 4. TRANSFORMER 4. B
5. TWO 5. PLUG and WIRE 5. A
6. REGULATOR
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