Amplifier – Where to Hook Up a Speaker in a Schematic

amplifieraudiointegrated-circuitspeakers

I'm working on a project that needs to drive a single speaker. I've used LM2879T chips in the past to drive two speakers, so I have a couple extra I'm trying to use for this single speaker project.

Since I'm using a single speaker, I've heard I should 'bridge' the two outputs of the amplifier. From the datasheet, it gives this example circuit. Maybe it is a silly question, but I'm not sure where I'm supposed to attach the speaker in this scenario. My best guess is that it takes the place of RL, but I wanted to check with others first.
enter image description here

Elsewhere in the datasheet, it gives this example for a typical two speaker setup, and it is fairly obvious where the speakers go.
enter image description here

Again, I'm using this chip just because I have it on hand. I've been eyeing some better options I would go for instead if this chip isn't worth it.

Thanks for any help!

Best Answer

The speaker connects where RL is on your bridge amplifier chip. The app note says 16 ohms so you know that a 16 ohm speaker can be safely connected. If your intended single speaker is lower than 16 ohm like say 4 ohm or 8 ohm then check the fine print in the data sheet. Remember that all these audio chips are pretty much voltage sources so lower speaker impedences will mean that the chip will try to make more current. It might not be able to do this. It might shut down, it may die young.