Here’s a 200W amplifier design for your home audio. It is a class AB amplifier. It is capable of delivering more than 200W at 4 ohms.
About the Circuit
There’s nothing special about the circuit, you can find it all over the internet nowadays.
Simulation
I simulated the circuit using simetrix software. You can download the simulation circuit on our download page so you can play with the circuit and component values. Be mindful on the power of the output transistors. You can increase output power by adding output transistors but you also need increase the supply voltage. You need to take note that the output transistor TIP3055 and TIP2955 can only have VCE max at 60V. In practice you don’t want to get near to that voltage. The safe supply voltage for this transistor should be around 45V.
PCB Design
The PCB design is simple and used 1 layer PCB only so anyone can build this project easily. You can also download the project on our download page if you want to modify it for your own requirements. My PCB design is simple and there are many rooms for improvements. The size of the filter 1000uf capacitor may be small in actual, you may need to check this before making the board. If you can change it with 2200uf capacitor then that would be better. But take note that this will be bigger capacitor. These capacitor are used to help supply power during big current draw. These high current draw usually happens during bass drum beats, especially if you set your bass to maximum. Supply voltage drops during bass drum beats due to high current draw and power supply output impedance.
These capacitors also helps reduce hum noise by filtering ripple voltage coming from the power supply.
The high current nodes such as power supply and output can be improved by making the trace wider. By making the trace wider on those nodes reduces voltage drops on those trace. This can improve bass performance.
3D Render
3D rendering is build-in on the KiCad software and this software is free!
Power Supply
This circuit can be powered by 24V up to 32V transformer. The transformer should be center tap and at least 8A for single channel.
image credits: interfacebus.com
NOTES:
If you want a very reliable design that doesn’t easily fail for years, the key is over designing. Design it to handle 200W and operate it at 100W and expect it to have longer life. This is because there is less stress and heat on each component if it is operating below its power handling. If you have computed that a resistor will consume 0.2W then use a 0.5W resistor or larger. Using a 0.25W resistor will still work but will eventually burn overtime.
DOWNLOADS
You can download the Kicad and simetrix project on our download page
