1. Voltage: DC 2.5-5.5V. 2. Output Power: 3W + 3W (at 4 ohm). 3. Noise ratio: 90dB. 4. Efficiency: more than 90 percent. 5. 2 channels 3W amplifier with PAM8403. 6. Output is CMOS BTL driver. 7. Cannot change any component parameters to protect IC. 8. The board can also be powered by 5V USB power supply or 4 x 1.5V battery. 9. It is perfect for MP3, MP4 and notebook.
