[Open Source] PCB Reference Materials Sharing for EDA-TPA3116

Based on the Class D digital amplifier chip TPA3116 Bluetooth amplifier, 2.0 dual-channel stereo lossless playback, supports wired and Bluetooth audio input. M18 Bluetooth 4.2 module, convenient and fast connection and playback, Bluetooth switch, switch at will. Function description AUX audio input + Bluetooth two-in-one HIFI-level filter 50Wx2 Bluetooth digital amplifier TPA3116D2 is a Class D amplifier IC launched by TI with very high index parameters. The modulation frequency can reach up to 1.2MHZ, and the distortion of high-power output is less than 0.1%. It has two audio source input modes, AUX and Bluetooth, two-in-one; the potentiometer adjusts the volume, with a switch, which is convenient for controlling the volume, and is very suitable for DIY speakers. 4.2 Bluetooth version, high transmission efficiency, longer transmission distance. Only when the audio input is sufficient and the power supply voltage and current are sufficient, can there be sufficient output power. The higher the power supply voltage, the greater the relative power, and speakers with different impedances have different output powers. In addition, there will be level indicators on the left and right, and different numbers of lights will light up depending on the size of the audio. Chip Description The chip is TI's Class D digital power amplifier chip TPA3116, output type: 2 channels (stereo) Maximum output power x number of channels at different loads: 50W x 2 @ 4 ohms Chip voltage - Power supply: 4.5 V ~ 26 V Features: differential input, mute, short circuit and thermal protection, shutdown Parameter Description The power supply part uses a DC-005 connector and a 5.08-2P terminal, and the power supply range is 12V~24V. LDO-7812 is used to power the pre-stage chip NE5532, and LDO-7805 is used to power the Bluetooth chip. The pre-stage amplifier chip is NE5532, a high-performance low-noise dual operational amplifier (dual op amp). The circuit does not add any mixing and polishing circuits, and basically maintains the original sound and color. The TPA3116 peripheral circuit is basically designed with reference to the official manual. (But note that the choice of inductor and capacitor will affect the sound quality) This circuit adds 10 LEDs of LM3915 of 2 channels as level indication. M18 Bluetooth module is an existing module bought from Taobao. The power supply adds LC filter circuit and 4-button adjustment circuit. Interface description 1. The power supply interface is DC-005 connector and 5.08-2P terminal. Note that the PCB has added the switch function. If necessary, the switch can be connected through the terminal. 2. The audio source input is a wired 3.5mm interface input and M18 Bluetooth input. It can be switched manually using SW1. (Originally, I wanted to do automatic switching, but I couldn't find relevant information) I found that Bluetooth and wired interfaces can be input at the same time, and simultaneous playback will occur. 3. 2.0 dual-channel, still using 2 2-pin 5.08 terminals to connect to two full-range speakers. Functional test 1. After 1 week, the sample was finally welded back. It turned over directly after welding, and the speaker could not work. After some research. It was found that the mute pin in the schematic diagram was connected incorrectly. The picture shows that this is the correct connection. The original version was connected to the above. Question 2, the schematic diagram of LM3915 was actually seen on Taobao. There is a problem with the input resistance of the sound source. After connecting, the sound of the speaker is very small. The reason is that the resistance is very small. The left channel is basically connected to the ground, which causes the sound of the speaker to be small. The solution is not to connect the 10R resistor or to increase the resistance. Finished product display 1, here manually pull the wire to change the mute foot circuit. 2. I use a speaker that has been with me for many years. It is used to crack walnuts and used as a hammer. The speaker is still usable and in good condition. It is already scarred. I use 15W impedance 8 ohms. Problem description The latest schematic diagram and PCB have been updated. Update content, 1, modify the mute foot circuit. 2, add a high current toggle switch. Use a better power supply to power the amplifier. It is recommended to use a 15V-24V, 3A or more regulated power supply. If you want to drive a high-power speaker, the amplifier chip should choose a large aluminum sheet for heat dissipation. The one in the picture is too small and cannot be suppressed.