Circuit diagram of 19 Watt amplifier using LA 4440 has been published here. This amplifier circuit is based on the IC LA 4440 developed by Sanyo. In this circuit, amplifier IC LA 4440 acts as bridge amplifier. This IC has an extra feature that is protection against thermal, over voltage and short circuits. Adequate heat sinks should be provided for this IC in PCB.
12 V DC power supply is used for powering this circuit. The power supply used should be able to deliver a current of 3A at least. This IC can with stand up to 25 V but it is safe to use up to 16V. A 4 ohm speaker is used here as load. This speaker load can be 8 ohm but in that case output power will become half of that with 4 ohm speaker.
LA 4440 Specifications
- Use a good quality PCB to assemble components for this circuit. Carefully understand the specifications of LA 4440 given above.
- This amplifier can deliver a 19 W Rms on a 4 Ohm speaker.
- The IC LA 4440 also incorporates an audio muting function but it is not required in this circuit.