Product introduction: PAM8403 Mini Class D Digital Power Amplifier Board 1. Working voltage: 2.5V-5.5V. Note: The power supply voltage should not exceed 5.5V, and the positive and negative power supply should not be reversed. 2. Speaker matching: 4-8 ohms, recommended: 4 ohms; speaker power: 2-8W. 3. You can use the 5V power supply of the computer USB port, or use the 5V power supply of the USB port of the mobile phone charger, or you can use the lithium battery power supply. 4. High efficiency 90%, under 4 load and 5V power supply, it can provide 3W (left channel) + 3W (right channel) output power. The efficiency of class A and class B power amplifiers is only about 30%, and class D power amplifiers are highly respected under the current green trend. 5. Class D power amplifier has high efficiency, will not affect the sound quality due to temperature rise, and does not need to add heat sinks, occupying a small volume. 6. The power amplifier board has a built-in noise cancellation circuit, and there is no popping noise when the power is turned on/off; the module has short-circuit overcurrent protection and overtemperature protection. 7. Board size: Ultra-micro volume: 1.85*2.11cm application: LCD TVs, monitors laptop portable speaker Portable DVD Players, Game Consoles Cell Phone / Speakerphone Precautions for use: Turn on the speaker first and then turn on the power, otherwise it is easy to cause damage to the chip; Since the digital volume control in the module has a large gain, do not let the audio signal input too large to cause the signal to cut and limit. Reminder: Dear customer: The module of our store is provided for electronic players with certain electronic knowledge to buy! And please carefully read the instructions for use or product introduction in the product description when purchasing the product. If you do not understand the use of the product, our company will not accept it. Please purchase with caution. Customer FAQ: 1. Can the mini digital power amplifier board 2*3W class D be powered by a computer? Answer: The power amplifier board can be powered by a computer, but it may generate noise (some customers have no noise), so it is recommended to supply power independently. 2. Is the mini digital power amplifier board 2*3W class D good with our speakers? Answer: The speakers in our store are only available for DIY players to try out, and the sound effect is not particularly good. Customers who pursue high sound effect can purchase them separately. 3. Why does the mini digital power amplifier board 2*3W class D make noise after the speaker is powered on? Answer: 1. If there is a whistling sound, it should be introduced by the audio input line, and a shielded line should be used as the audio input line. Also, the audio input line should not be left floating, and the audio source should be connected. 2. Another reason may be that the power supply is not good, and some switching power supplies have a lot of interference, which is caused. 3. Try to lower the sound, or it may be that the audio signal input is too large and the signal is cut and limited. Noise suppression, in the case of no input audio, the ear is close to the speaker and can not hear any noise, two-channel stereo, 5V power supply can output 3W+3W power, can directly drive 4, 8 small speakers, the output power Large, full of energy, good sound quality. The latest class D digital power board without LC filter can directly use the USB power supply of the computer. Double-panel wiring can properly solve the ground potential balance and crosstalk between channels caused by wiring. The ultra-miniature design can be easily placed in a small space inside various digital products, with high amplification efficiency. The whole board is welded by machine, and the welding quality is comparable to that of manual soldering iron welding! Note: The "negative" of the left and right channel output terminals cannot be connected in parallel, otherwise the IC will be burned, and the speaker (load) should be connected before powering on. Ultra-small size: 1.85*2.11cm, about the size of a dime coin Please note: The "negative" output terminals of the left and right channels cannot be connected in parallel, otherwise the chip will be burned, and the speaker (load) should be connected before powering on. Rated working voltage 2.5-5V, limited working voltage 5.5V