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Cheap amplifier board, what do all the connections mean please Answered

I bought a cheap amplifier board based on the PAM8403 chip


most of the connections make sense, from top to bottom in the main picture, two speakers, then power, then sw and gnd, followed by the left right ground which I assume is stereo input.

I have no idea what the SW and GND refer to, can anyone help me out here?


Josehf Murchison

1 year ago

R+ is right speaker positive

R- is right speaker negative

L+ is left speaker positive

L- is left speaker negative

GND is ground or negative source voltage

5v is 5 volts source voltage

SW is switch my guess to a switch and source voltage try the circuit without SW connected.

GND is left audio ground

LIN is left audio positive

GND is right audio ground

RIN is right audio positive

Do not connect LIN and RIN or their grounds to the same audio source.

The instructions on the page is important.

Matters needing attention:
Power positive and negative can not be reversed, the power supply voltage can not exceed 5.5V, these two violations will cause IC damage.
On-chip high gain buffer, can not change any component parameters on board, the parameters do not meet will lead to IC damage.
Input line, please use the shielded line as far as possible, can play an anti-interference role, eliminate the noise of the current of the wave.
The output is CMOS tube BTL drive mode, the negative electrode of the left and right speakers can not be connected together, that is, the 4 lines of the speaker are completely independent, and no joint connection is allowed!


Reply 1 year ago

go with this link, didn't show up when I posted my last post hehe


1 year ago

Same board slightly different places and missing the mute button, but the wiring is the same