Features:

• Working voltage: 2.5V-5.5V. Note: The power supply voltage should not exceed 5.5V, the power of positive and negative do not reversed.
• The speaker is equipped with: 4-8 Europe, recommended: 4 ohms; Speaker power: 2-8W.
• You can use the computer USB port 5V power supply, or use a cell phone charger USB port 5V power supply, you can use a lithium battery power.
• The high efficiency of 90%, under 4 load and 5V supply conditions, can provide 3W (left channel) + 3W (right channel) output power. Efficiency amplifier Class A, Class B and so only about 30%, Class D amplifier respected in todays green trend.
• D class high power amplifier efficiency, not because of temperature affect the sound quality, but without additional heat sink, taking up very small.
• The amplifier board built noise cancelling circuit, no noise when the power is turned on / off; module with short circuit current protection and over-temperature protection. Note: The first speaker is turned on and then turned on the power, or likely to cause damage to the chip; the module great digital volume control gain, so do not let the audio signal input signal is too large leaving cutting limit. Left and right channel output of the "negative" and can not be connected together, otherwise it will burn IC, and electricity should be preceded connected speaker (load).