Aim:
To present and study about when the base voltage of transistor is zero (or negative ), the transistor is cut off and act as an open switch.
Theory:
when the transistor switches "Off", the current fllowing through the relay the coil decreases and the magnetic field collapse. However stored energy within the magnetic field has to go some where and a reverse voltage is developed across the coil as it tries to maintain the current in the relay coil.
COMPONENTS REQUIRED:
Npn transistor :
Npn transistor are a type of bipolar transistor with three layers that are used for single amplification.
2.5 pin relays:
A relays is an electrically operators switch.5 pin relays provide 2 pin(85 & 86) to control the coil and 3 pins(30,87 & 87A) which switch power between two circuits.
Resistros:
A resistor is a passive two-terminal electrical component that implement electrical resistance as a circuit element.
LED :
LED stands for light emitting diode. LED lighting products produce light up to 90% more efficiently than incandescent light bulbs. the major use of LED are to illuminate objects and even place.
5.Switch :
A switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electrical current or diverting it from one conductor to another.
OBSERVATION:
Relays and transistor are most often used for this purpose.When using the transistor as switch , a small base current controls a much larger collectory load current.
Relays take advantage of fact that when you pass an electric current through a wire , a magnetic field is generated surrounding the wire as well.
*FORMULAS-
1.Transistor base current:
Ib = Ic\B
Ib - Input Base current
Ic - output collector current
B(beta) - current gain beta
2.Transistor base resistance:
Rb = Vin - Vbe\ Ib
Rb = Base resistor
Vin = voltage input
Vbe = Base emitter voltage
Ib = input base current
WORKING PRINCIPLE:
The transistor can be used as a switch . The schematic below shows the light Emitting Diode(LED).
Procedure:
When the switch at the base terminal is open, no current flows through the base so the transistor is in the cut off state .
Therefore, the transistor acts as an open circuite and the LED becomes off.
When the switch is closed, base current starts flowing through the transistor and then drives into saturation, which results in Led to turn ON.
Resistors are placed to limit the current through the base and LED. it is also possible to vary the intensity of LED by varying the resistance in the base current path.
CONCLUSION:
No input power is required to keep the switching state of field effect transistor. A current is running for short span of frequency ,The higher the input power requiered to control the FET.
Referance :
1. https://youtu.be/BgLQucEzqHg
2. https://youtu.be/ERy8NC_Kzrk
3. https://youtu.be/iJshbz5JYuw
4. Wikipedia(google)
Sankethgowdas
commented
1 year ago
Aim: To present and study about when the base voltage of transistor is zero (or negative ), the transistor is cut off and act as an open switch.
Theory: when the transistor switches "Off", the current fllowing through the relay the coil decreases and the magnetic field collapse. However stored energy within the magnetic field has to go some where and a reverse voltage is developed across the coil as it tries to maintain the current in the relay coil. COMPONENTS REQUIRED:
2.5 pin relays: A relays is an electrically operators switch.5 pin relays provide 2 pin(85 & 86) to control the coil and 3 pins(30,87 & 87A) which switch power between two circuits.
Resistros: A resistor is a passive two-terminal electrical component that implement electrical resistance as a circuit element.
LED : LED stands for light emitting diode. LED lighting products produce light up to 90% more efficiently than incandescent light bulbs. the major use of LED are to illuminate objects and even place.
5.Switch : A switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electrical current or diverting it from one conductor to another.
OBSERVATION: Relays and transistor are most often used for this purpose.When using the transistor as switch , a small base current controls a much larger collectory load current. Relays take advantage of fact that when you pass an electric current through a wire , a magnetic field is generated surrounding the wire as well. *FORMULAS- 1.Transistor base current: Ib = Ic\B Ib - Input Base current Ic - output collector current B(beta) - current gain beta 2.Transistor base resistance: Rb = Vin - Vbe\ Ib Rb = Base resistor Vin = voltage input Vbe = Base emitter voltage Ib = input base current WORKING PRINCIPLE: The transistor can be used as a switch . The schematic below shows the light Emitting Diode(LED). Procedure:
CONCLUSION: