Bipolar Junction Transistor ( BJT )

Bipolar transistors are semiconductor devices consist of three electrodes; the emitter, base and collector. Like diodes, bipolar transistors can be constructed of silicon or germanium but silicon is the most popular. Bipolar transistors are commonly used as amplifier and electronic switch. There are two types of bipolar transistor, NPN and PNP.

Diode

A semiconductor diode is an electronic component consists of two electrodes, the anode and the cathode. The anode (A) is the positive electrode of diode while cathode (K) is the negative electrode. The anode allows only positive charges and blocks negative charges while cathode allows negative charges and blocks positive charges. The diode acts as one-way valve for the flow of current. This means that the diode allows current to follow through it in one direction and blocks its flow in the other direction.

Active-Matrix Organic Light-Emitting Diode ( AMOLED)

AMOLED or Active-Matrix Organic Light-Emitting Diode ( AMOLED) is a display technology usually used for mobile devices (cellular phones, MIDs, laptops, etc) and televisions. AMOLED display contains matrix of OLED pixels that have been placed into TFT (thin film transistor) array. It serves as a series of switches to control the current traveling to each individual pixel.

Resistor Color Codes

Resistor Color Codes Part 1

Types of Capacitor

Capacitor can either be fixed or variable. Fixed capacitor has a definite capacitance value that cannot be changed or varied. Variable capacitors are those with multiple capacitance values.

Capacitor

What Capacitor Is?
Capacitor is an electronic component that has the ability to store a specific amount of capacitance. Capacitance (C) is the ability of the capacitor to store electrical energy in an electrostatic field.

Testing Resistors with an Ohmmeter

Resistors condition can be checked using the ohmmeter function of the multitester. The possible troubles of resistors are open, increased resistance value and decreased resistance value. Below are the guides that you should follow to test the condition of the resistor.

Things to be Considered in Drawing Symbols and Diagrams

Drawing circuit diagrams is not a hard task but it will take some practice to make a neat, clear and quality diagrams. This is a useful skill for a would-be electronic draftsman like you. You will surely need to draw electronic diagrams if you plan to design your own circuits in the future. Below are some things that you should consider when constructing diagrams.

Types of Diagrams

There are several diagrams used in electronics, the most commonly used are the block diagram, schematic diagram and the component layout. Block diagrams are used to give you the overall view of the circuits by breaking them down into smaller sections or blocks. Each block or section performs a particular function and the block diagram shows how they are connected together. As you can see on the illustration below, it does not show the components used within a block, only the inputs and outputs are shown.

Reference ID

Most schematic symbols are accompanied by labels. This “labels” maybe a combination of the following; reference ID, part number and value.

Reference ID is an identifier, such as “R1”, “C4” or “Q4”. The letter represents the type of component. The commonly used letters are R for resistor, C for capacitor, L for inductor, D for diode, Q for transistor and IC for integrated circuit. If there are several components of the same type in a circuit, the numeral suffix (as an example R2) is added to identify the particular component.