Dual channel stereo output 3 W + 3 W power Class D amplifier.
Features:

1. high amplification efficiency 85%
2. can directly drive 4 ohm/8 ohm small speakers
3. good sound quality & noise suppression
4. unique without LC filter class D digital power board
5. can use computer USB power supply directly
6. low THD+N
7. short circuit protection
8. thermal shutdown

Specifications:

1. operating voltage: 2.5 to 5 VDC
2. connections: solder connections
3. sound processor: PAM8403
4. dimensions: 23 x 16 x 2 mm

pam8403_datasheet.pdf

ce_rohs_open.pdf

wpi411a4v01.pdf