An audio amplifier circuit serves the purpose of increasing the amplitude of an audio waveform. without changing other properties of the waveform such as frequency or wave shape. They are one of the most common in use circuits when it comes to electronics and perform a wide variety of functions in a great many electronic systems. In this project, we are going to design a simple 2-watt audio amplifier circuit using TBA820 audio amplifier IC
The TBA820 audio amplifier circuit is a monolithic integrated audio amplifier in an 8-lead dual-in-line plastic package. It seamlessly functions as a low-frequency class B power amplifier with a big range of supply voltages: 3V to 16V. In portable radios, recorders, players, etc. Its main features are a small number of extra components required, good ripple rejection, no distortion & low power dissipation.
Hardware Components
The following components are required to make Audio Amplifier Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | Breadboard | – | 1 |
| 2. | Battery | 9v | 1 |
| 3. | Connecting Wires | – | 1 |
| 4. | Amp IC | TBA820 | 1 |
| 5. | Speaker | 4 ohm | 1 |
| 6. | Resistor | 10k, 120, 56, 1ohm | 1 |
| 7. | Polar Capacitors | 220μF, 470μF, 100μF, 47μF | 1,1,1,1 |
| 8. | Non-Polar Capacitors | 100nF, 220pF | 1,2 |
| 9. | Condenser MIC | – | 1 |
TDA820 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TBA820
Audio Amplifier Circuit
Working Explanation
The heart of this circuit is a TBA820M monolithic audio amplifier IC. The input is taken through a suitable microphone & is delivered to an output audio transducer.
R1 sets the input impedance of this circuit at 10K. C2 and R2 control the gain of the amplifier. Both R3 (1 ohm) and C3 (220μF) maintain a good sound. C3 controls the ripple rejection rate. C6 is the output coupling capacitor & connects the output signals to the speaker. C1 filters the noise ripple from the power supply voltage.
Applications
- Audio power amplifiers are used in almost all electronic devices such as microwave ovens, headphone drivers, televisions, and mobile phones.
- An important part of live music production & recording.
- A common part of home entertainment devices such as mono & stereo speakers for home theatre setups.
