Explain transistor as amplifier.
Asked by Pratibha Roy
| 14th Feb, 2012,
10:48: AM
??
The Transistor as an Amplifier
Amplification is the process of linearly increasing the amplitude of an electrical signal.
A transistor can act as an amplifier directly using the gain, b.
Keep in mind that when a transistor is biased in the active (linear) region, the BE junction has a low resistance due to forward bias and the BC junction has a high resistance due to reverse bias.
i) DC and AC quantities
Amplifier circuits have both ac and dc quantities.
Capital letters are used will be used for both ac and dc currents.
Subscript will be capital for dc quantities.
Subscript will be lowercase for ac quantities.
ii) Transistor amplification
A transistor amplifies current because the collector current is equal to the base current multiplied by the current gain, b.
Base current (IB) is small compared to IC and IE.
Thus, IC is almost equal to IE.
The Transistor as an Amplifier
Amplification is the process of linearly increasing the amplitude of an electrical signal.
A transistor can act as an amplifier directly using the gain, b.
Keep in mind that when a transistor is biased in the active (linear) region, the BE junction has a low resistance due to forward bias and the BC junction has a high resistance due to reverse bias.
i) DC and AC quantities
Amplifier circuits have both ac and dc quantities.
Capital letters are used will be used for both ac and dc currents.
Subscript will be capital for dc quantities.
Subscript will be lowercase for ac quantities.
ii) Transistor amplification
A transistor amplifies current because the collector current is equal to the base current multiplied by the current gain, b.
Base current (IB) is small compared to IC and IE.
Thus, IC is almost equal to IE.
Answered by
| 14th Feb, 2012,
11:09: AM
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Sign Up
Verify mobile number
Enter the OTP sent to your number
Change