Doping:
The conductivity of silicon and germenium can be drastically increased by the controlled addition of impurities to the intrinsic (pure) semiconductor material. This process, called doping, increases the number of current carriers (electrons or holes).
N Type Semiconductor:
To increase the number of conduction band electrons , pentavalent impurity atoms like arsenic (As), phosphorus (P), bismith(Bi) and antimony (Sb) are added.
Each pentavalent atom leaves an extra free conduction electron after combining with the silicon atom forming covalent bond.As pentavalent atom gives an electron so called donar atom.
The number of conduction electrons can be controled by the impurities ato added to silicon.
Most of current carriers are electron,silicon doped with pentavalent atoms is an n-type semiconductor material.The electrons are called majority carriers.There are also some holes when electrons are paired when thermally processed.These holes are called minority carriers.
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Showing posts with label high voltage power supply. Show all posts
Showing posts with label high voltage power supply. Show all posts
Full Wave Rectification
A full-wave rectifier converts the whole of the input waveform to one of constant polarity (positive or negative) at its output. Full-wave rectification converts both polarities of the input waveform to DC (direct current), and is more efficient.
Full wave rectification:
The positive half cycle:
During the positive half cycle of the supply, diodes D1 and D2 conduct in series while diodes D3 and D4 are reverse biased and the current flows through the load as shown below
The negative half cycle:
During the negative half cycle of the supply, diodes D3 and D4 conduct in series, but diodes D1 and D2 switch of as they are now reverse biased. The current flowing through the load is the same direction as before.
Full wave rectification for smoothing DC:
With the full wave rectification we get the pulsating DC with the ripples.For smooth DC we use capacitors to remove ripples.
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Full wave rectification:
The positive half cycle:
During the positive half cycle of the supply, diodes D1 and D2 conduct in series while diodes D3 and D4 are reverse biased and the current flows through the load as shown below
The negative half cycle:
During the negative half cycle of the supply, diodes D3 and D4 conduct in series, but diodes D1 and D2 switch of as they are now reverse biased. The current flowing through the load is the same direction as before.
Full wave rectification for smoothing DC:
With the full wave rectification we get the pulsating DC with the ripples.For smooth DC we use capacitors to remove ripples.
Read More!
Kirchhoff's Voltage Law
What is loop?
A loop is any path that goes from node to node and returns to the starting node, passing only once through each node.
Kirchhoff's Voltage Law:
The sum of the voltage drops around any loop equals the sum of the voltage rises.
or
The algebraic sum of all voltage drops around any loop equals zero.
Mathematically,
v1 + v2 + v3 + v4 = 0
or
Parallel Connection:
Two or more elements are in parallel when their terminals are connected to the same pair of nodes.
Also that elements in parallel have the same voltage across each one of them.
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A loop is any path that goes from node to node and returns to the starting node, passing only once through each node.
Kirchhoff's Voltage Law:
The sum of the voltage drops around any loop equals the sum of the voltage rises.
or
The algebraic sum of all voltage drops around any loop equals zero.
Mathematically,
v1 + v2 + v3 + v4 = 0
or
Parallel Connection:
Two or more elements are in parallel when their terminals are connected to the same pair of nodes.
Also that elements in parallel have the same voltage across each one of them.
Read More!
Kirchhoff's Current Law
what is node?
A node is any connection point of two or more circuit elements.
Kirchoff's current law:
The sum of the currents leaving any node equals the sum of the currents entering that node.
or
The algebraic sum of all currents into any node equals zero.
mathematically,
i1 + i4 = i2 + i3
or
Series Connection:
Two or more elements are in series when each node connects just two elements.
Also that elements in series carry the same current.SCYT328STX6Y Read More!
A node is any connection point of two or more circuit elements.
Kirchoff's current law:
The sum of the currents leaving any node equals the sum of the currents entering that node.
or
The algebraic sum of all currents into any node equals zero.
mathematically,
i1 + i4 = i2 + i3
or
Series Connection:
Two or more elements are in series when each node connects just two elements.
Also that elements in series carry the same current.SCYT328STX6Y Read More!
