Introduction:
The amplifier is an electronic device that magnifies the strength of the input signal by transmitting the energy to an incoming input by means of any power source at a controlled level. The signal may be voltage, power, or current. Amplifiers are generally used in communication systems that comprise analog signals. They can be classified according to their functioning as DC (direct current) amplifiers, audio frequency amplifiers, radio frequency amplifiers, and UHF, VHF, or SHF amplifiers.
Here we will discuss the working and designing of the audio amplifier with an output power of 7 watts which means the maximum load the circuit can drive is 7 watts. An audio amplifier as the name describes is a device that amplifies the audio signal received from any input source such as a radio receiver or any electronic instrument to produce a strengthened signal at the output to drive a loudspeaker or headphone. Few key characteristics of an audio amplifier that define its quality are, output power, gain, signal-to-noise ratio, distortion, impedance, and frequency response.
Hardware Components
The following components are required to make 7 Watt Audio Amplifier Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | Amplifier IC | TDA2003 | 1 |
| 2. | Electrolytic Capacitor | 10uF, 470uF, 1000uF | 1 |
| 3. | Ceramic Capacitor | 100nF, 1822pF | 2, 2 |
| 4. | Resistor | 1, 47, 100, 470) Ohms | 1 |
TDA2003 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TDA2003
7 Watt Audio Amplifier Circuit
Working Explanation
This simple amplifier circuit uses TDA2003 IC and a few passive components. TDA2003 is a general-purpose amplifier IC that has a maximum power output of 10W and maximum current output of 3.5A. It can handle the high current of up to 5A for short time duration and has built-in short circuit protection and overload protection circuit.
Pin1 of the IC receives the input signal through the input DC decoupling capacitor. The resistor (100Ohm) and capacitor (1822pF) in series determine the upper cut-off-frequency, the two resistors in series i.e. 47 Ohms and 470 Ohms in combination set the gain of the amplifier and the capacitor of 100nF and resistor of 1 Ohm amplifies the stability at higher frequencies. The output is received at pin4 through a coupling capacitor.
In the end, the amplified signal is obtained at the output which can drive any loudspeaker or headphones, etc.
Applications & Uses:
Audio amplifiers find their applications in various ways. Some uses are mentioned as follows:
- Most sound systems use audio amplifiers to strengthen the output signal from speakers or headphones.
- Many musical instruments have internal audio amplifiers installed in them.
- Amplification of audio is required for the transmission of signals over a long-distance range.
- Audio amplification also finds its use in the wireless transmission of data.
- Home theater or Cinema Theater has audio amplifiers to deliver the loud sound required to attract the audience.
