Operating a class D amplifier is really easy and on the other hand it is very difficult to DIY one, because the power supply section and the PWM section is really complicated. Any different value component can produce hum and destroy the overall performance. I am working on the existing very stable class D amplifiers designs. But in order to explore more about the amplifiers I got my hands on Wuzhi 50+50w Hi-Fi amplifier kit. Which comes with a TPA3116 amplifier IC from DfRobot. The kit is listed on Dfrobot and named as 502C Hi-Fi amplifier.

This class D amplifier has great frequency response, and very stable output to high, low and mid. Audio filter is made using LC circuit on output thus having a rigid current carrying capacity. In the datasheet 26volt standard voltage is mentioned but it also works on 12volts. Although you would not get the full fledge performance boost on 12volt.

In last I will also show my designed prototypes which are assembled by JLCPCB SMT assembly service. JLCPCB is the China based PCB manufacturer provide SMT assembly, PCB prototypes, Stencil, 3-d printing and PCBA service. Register now to JLCPCB and get free $54 new user coupon.

Unboxing and parts:

In the package you will get an amplifier board, acrylic protection sheets, heatsink, 12v DC pin, screwdriver, nuts and bolts. Means it is a good package and you did not need any external part for assembly. Even the recommended screwdriver is given in the box.

Specifications and features:

This amplifier comes with stereo 5.0 BT and AUX compatibility. The same JL series IC is used for Bluetooth. You can see my projects on this IC from here. One integrated circuit TPA3116 is used which comes with 100W max power draw. The output is divided in two channels and used as stereo. You will get on board power ON/OFF switch and volume control. It works flawlessly without any external noise.


First of all, mount the heatsink on the IC, because this IC runs very hot under peak performance. The given heatsink has sticky nature which can be directly pasted on the chip with proper insulation to surrounding.

Now tight the acrylic sheets on both side of the amplifier, this will cover the entire board and protect all the joints from short circuit. You can also place this amplifier in a housing using the same acrylic. Now everything is done, just give 24v Dc to the amplifier and use stereo speakers on the output to this.

Working of amplifier:

The amplifier is very loud and class D is working very stable under full load. The output is balanced due to high power and better-quality LC filter. Never use linear power supplies with class D amplifier. The class D amplifiers works on a single power supply of 0-24 and the output is just a square wave filtered to get the sound. 

In real the high frequency operation of these amplifier causes some serious problems if you are a music lover. In that case you can use class A and AB amplifiers. By the way, Class D has some great lead in terms of efficiency (90%) and low heat.

My circuit diagram and amplifier:

Last month, I also designed an amplifier using the same integrated circuit TPA3116, I tried a lot of schematics and different configuration and in last I was able to build my own single channel. You can see the full details from here.

These amplifier are made using JLCPCB SMT assembly service because some parts are not available at my place. JLCPCB offers a very affordable PCB Prototyping and SMT assembly service. The SMT assembly service is the best one because the provide fastest PCB assembly using LCSC and EasyEDA like partners. You can also explore more service by visiting the official website JLCPCB.com.

DF robot:

DF robot the product-based company which deals in electronics like sensors, microcontroller and robotics. They own a beetle series of microcontrollers having a very small form factor in the same performance. You can see the more detailed on DF microcontroller from here. Buy 502C Hi-Fi...

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