Here is a simple circuit of “20-Watt Audio Amplifier” using IC TDA2003 to amplify weak audio signal. Various types of amplifier circuit have already posted in amplifier circuit section.
The IC TDA2003 contains pre-amplifier, driver amplifier and output amplifier internally. Basically, TDA2003 is an improved version of TDA2002 with various features like very low harmonic distortion and high output current capability.
Circuit Description of 20-Watt Audio Amplifier using TDA2003
The circuit of 20-Watt Audio Amplifier using TDA2003 shown in figure 1, build around TDA2003 amplifier IC. For flawlessly working various other complementary components are also used. The input audio signal is given to the non-inverting pin (pin 1) of IC through coupling capacitor C1. Voltage supply VCC is given to pin no 5 where pin 3 is connected to ground.
The output is obtained at pin 4 which is connected to the speaker through other coupling capacitor C3. A series network made from resistor R3 and capacitor C4 is connected after coupling capacitor C3. This network is used as filter circuit which is used in order to high frequency noise. This network made form resistor R3 and C4 is not compulsory and is only used when it is prone to high frequency noise.
Note: For proper 20-Watt output power, input voltage of 12V of 5A must be given to pin 5, which may cause heating effect thus, a proper heat sink must be used.
PARTS LIST OF 20-WATT AUDIO AMPLIFIER USING TDA2003
|Resistors (all ¼-watt, ± 5% Carbon)|
|R1 = 2.2 Ω
R2 = 220 Ω
R3 = 1 Ω
|C1 = 4.7 µF/16V [Electrolytic Capacitor]
C2 = 220 µF/16V [Electrolytic Capacitor]
C3, C5 = 1000 µF/16V [Electrolytic Capacitor]
C4 = 0.1 µF [Ceramic Capacitors]
|IC1 = TDA2003|
|LS1 = Loudspeaker|