[Chenghang PCB Competition] Audio power amplifier circuit

1. Project description:

This is a power amplifier project based on the LM4766 audio power amplifier. At the same time, this is an excellent work in a school-level PCB design competition. The project draws the schematic diagram based on the official TI manual, and then hands it over to the students for PCB design.

2. Chip introduction:

The LM4766 is a stereo audio amplifier capable of providing a single channel 40W output.

The LM4766's performance, utilizing its own Peak Instantaneous Temperature (Ke) (SPiKe) protection circuitry, places it in a class above discrete and hybrid amplifiers, providing an intrinsic, dynamically protected Safe Operating Area (SOA). Spike protection means these components are protected at the output against overvoltage, undervoltage, overload, including thermal runaway and transient temperature spikes.

Each amplifier within the LM4766 has an independent smooth transition fade in/out of mute, minimizing output pop-up. The IC's extremely low noise floor in the UV and its extremely low THD+N value of 0.06% power rating make the LM4766 best suited for high-end stereo TV or small form factor systems.

Type: Class AB
Output Type: 2 Channels (Stereo) Maximum Output Power
at Different Loads Silent, thermally protected Operating temperature: -20°C ~ 85°C (TA) Low external component count Quiet fade/silent mode

3. Application:

1.Typical applications:

2. Bridge application:

3.Power supply:

It is recommended to use 18V AC input. In the actual measured version, the heat dissipation is good. When the wire is tinned, a single channel can reach about 35W.

4. A handmade board in the laboratory

4. Competition requirements

1. In order to test the students' PCB practical operation, we have modified the package pad size of LM4766. If you want to use this open source project, please check the package of LM4766 and replace it with the chip package provided by Lichuang.

2. Since the chip has high power, please dissipate the heat of the board chip and increase the trace width according to the needs to avoid excessive current for a long time.

3. This project is a PCB design competition entry. If there are any deficiencies in the design of this project, you are welcome to make changes according to your needs.