The circuit diagram given below represents 40W audio amplifier. This 40W power amplifier circuit is designed using IC TDA 2030 and two transistors as main components. The IC TDA 2030 is the core part of this circuit because it plays the main role in voltage amplification. The job of current amplification is done by the two transistors. Adequate heat sinks should be provided for IC and both transistors.
The input signal is fed to the non- inverting terminal (pin 1) of TDA 2030 IC through the decoupling capacitor C5 (470 nF). When voltage amplification is performed by TDA 2030, the power supply current to IC changes with respect to the variation in the input signal. The variations in positive and negative supply pins of the IC are coupled to transistors Q1 (BD 712) and Q2 (BD 711). These transistors are connected complementary to each other in circuit so that they perform current amplification.
Power supply for the circuit can be 12V to 40V. Use 40V supply and 4 Ohms speaker for maximum output. To optimize the circuit performance, input and output grounds must be properly decoupled.
- Use a good quality PCB to assemble components for this circuit.
- Make PCB tracks broader through which high current flows.