Rectifier The electric power is usually available in a.c supply. The supply voltage varies sinusoidal and has a frequency of 50Hz and used for different purposes such as lightning, heating and electric motors. But there are many applications such as electronics circuit where d.c supply is needed. When such a d.c supply is requires, the … Read more
Transistor as an Amplifier The transistor amplifier circuit is shown in the figure ,shows the common emitter npn amplifier circuit. VBB is connected in the input circuit in addition to the signal voltage. This d.c voltage is known as bias voltage and its magnitude is such that it always keeps the emitter-base junction forward biased … Read more
Transistor connections There are three leads in a transistor i.e. emitter ,base and collector terminals. When a transistor is to be connected in a circuit, we requires four terminals; two for the input and two for the output. This difficulty is overcome by making one terminal of the transistor common to both input and output … Read more
Transistors Definition: A transistor consists of two PN junctions formed by sandwiching either p-type or n-type semiconductors between a pair of opposite types. There are two types of transistors: n-p-n transistor p-n-p transistor An n-p-n transistor is composed of two n-type semiconductors separated by a thin section of p-type in fig (i).A p-n-p transistor is … Read more
Zener Diode A properly doped crystal diode which has a sharp breakdown voltage is called a Zener diode. Zener diode is a special type of semiconductor diode which works in a breakdown region. A Zener diode uses reverse(VR/IR) characteristics for its operation. Therefore ,it is always reverse connected in the circuit i.e. it is always … Read more
Volt-Ampere Characteristic of a PN Junction Diode Volt-ampere or V-I characteristics of PN junction diode is the curve between voltage across the junction and the circuit current. Usually voltage is taken along x-axis and current along y-axis. The figure below shows circuit arrangement for determining the V-I characteristics of a PN junction diode. The characteristics … Read more
Diode Diode are the electronic components which conducts current in one direction(unidirectional).A PN junction is known as a semiconductor diode. Silicon and germanium are used in manufacturing the diode. The schematic symbol of diode is represented by The arrow in the symbol indicates the direction of easier conventional current flow. A diode has the two … Read more
N-type semiconductor When a small amount of pentavalent impurity is added to a pure semiconductor it is known as n-type semiconductor. The addition of pentavalent impurity provides a large number of free electrons in the semiconductor crystal. Pentavalent impurity: Arsenic, Antimony Such impurities which produce n-type semiconductor are known as donor, impurities because they donate … Read more
What is P-type semiconductor? when a small amount of trivalent impurity is added to a pure semiconductor, it is called p-type semiconductor. The addition of trivalent impurity provides a large number of holes in the semiconductor. Trivalent impurities: Gallium, Indium, Boron ,Aluminum The impurities which produces p-type semiconductors are known as acceptor impurities because the … Read more