Amplifier Circuit Diagrams

Power Amplifier Circuit – 25 Watts Schematic Circuit Diagram

The 25-watt Audio power Amplifier circuit was designed by using IC TDA 2040 (25-watt hi-fi audio power amplifier) from ST. It is a monolithic Integrated circuit that comes in a petawatt V package so it occupies less space in PCB, and it can be used as a Class AB amplifier.


Here is the diagram of a 25 Watt power amplifier circuit made of  TDA2009 IC. TDA2009 IC is a hi-fi Class AB stereo amplifier in the multi-watt package. It is actually a dual audio power amplifier that is designed specifically for very good quality stereo applications. TDA2009 is used in amplifier circuits as the electronic components associated with the circuit are abundantly available and are economical too. The IC is integrated with two identical amplifiers that can produce an output of 12.5 watts per channel on 4 Ohms load. Here the two channels are bridged to get a single output channel weighting 25 W.

TDA 2009 IC has also built-in features such as short circuit protection, thermal protection, overload protection, etc using very low external components. The most interesting factor I see about this IC is that it does not require a dual supply.

Components List

Power Amplifier Circuit Diagram and Power Supply Circuit Schematic

Power Amplifier Circuit Diagram and Power Supply Circuit Schematic

TDA 2009 Power Amplifier Supply

TDA 2009 Power Amplifier Supply Schematic Circuit Diagram


  • Do not connect more than 24 V to TDA2009.
  • If a 5-ampere bridge is not available make one using four 5 A diodes.
  • Fit a proper size heat sink to TDA2009
  • Do not operate the circuit without a heat sink.
  • For volume control connect a 10K pot
  • All capacitors in this circuit must be rated above 25 V.
  • Capacitors with + mark are electrolytic and that lead will be positive. Other capacitors will be normally ceramic. If there is an exception that will be given there in the circuit or parts list. This law applies to all circuits on this site.

Related Articles

Leave a Reply

Your email address will not be published.

Back to top button