An audio amplifier is a device that multiplies an applied input signal amplitude to a level that may be much higher than the input signal. The input is given in the form of audio or music. The amplifiers are classified into classes like class A, class B, class AB, class C, and class D. Here we are going to discuss the first type of amplifier, i.e., the class A amplifier, and also learn how to build a single transistor class A amplifier circuit.
Amplifiers are generally very efficient because these amplifiers conduct only during the presence of an input signal, and they only boost input signals. Single transistor amplifiers is very low power testosterone cypionate for sale amplifiers and consume very little energy; even a single battery of low amperes can be used to run it for many hours.
We want to make clear these types of amplifiers are very easy to build, but the quality of the mini amplifier circuit is not very good.
Single-transistor amplifiers are also known as common-emitter amplifiers and are widely used due to the very easy circuit to design. A simple single-transistor amplifier dramatically boosts audio input to output.
Components required For one transistor Amplifier
- Transistor 1: any NPN type
- A resistor 4.7k
- Speaker 3w 4 ohm
- capacitor 10uf 16v
Circuit Diagram 1
Calculations
Vout = R2 * R1 + R2 * Vin
Rearrange the formula.
R1 = R2(Vin * Vout − 1)
Here the speaker is R2, which is 8Ω, Volts in (VIN) is 5V and Vout is 2.83V. So alternate the values, and we have:
R1 = 8(52.83 − 1)
12-volt amplifier
The given below circuit diagram is perfect for 12 volts. The quality and output of this circuit is much better than the circuit given above for 4 volts. In this way, you can change testosterone undecanoate 250 speakers as well as resistors according to the formula.
Amplifier circuit diagram
Given below is the circuit diagram for a 12-volt single-transistor amplifier circuit.
9-volt Circuit Diagram
The circuit diagram given below is the calculated form of a single transistor amplifier for a 9-volt battery. It is also a low-power and low-energy-consumingamplifier.