Suggestion for a chip amp to pair with PCM1798 in a toy music box

Hello, i'm a beginner in circuit design and audio circuit, but i want to make my first toy project.
I'm planing to make a simple board that will play sound from sdcard, and i chose pcm1798 to be the DAC chip. I don't know whether i can connect the output of that chip directly to a speaker and good with it, or i need an amp chip.
 
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Welcome to diyAudio.

Perhaps a simple LM386 based chip might suit. It has high gain and low power consumption and should be perfect for what you describe. Do a web search for LM386 chip amps.

Screenshot 2023-06-08 090157.png

LM386 Data Sheet
 
386 is a headphone amp, IIRC. Only 750 mW, enough for a small unit.
Decide how much power is needed, and go from there.

Chinese 2822 are common in computer speakers. As are many chip amps found in small devices.
Or you could use a FM module, DAC + many more features like Bluetooth.
You also need to tell us single or dual channel, and speaker details.
 
For my project, a simple speaker around the loudness of a laptop speaker is enough, so about 1W of power. My DAC chip can deliver 2 channels, so a 2 channels amps is always welcome. Sound quality is a concert too but i don't think i need anything that is better than a laptop speaker.
 
Then I think 386 is enough, use one per channel (IIRC it is a mono chip, may be mistaken).
Or a 6283 running one / both channels, mighty mouse at 2 watts each ...and the TDA 2822.

You may find one in your old computer speakers, the power supply, speakers and controls can be recycled.
 
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Then the LM386, LM1875, and TDA2020 spring to mind. Of those, I'd probably go with the LM1875. It would also be an excellent learning opportunity if you wanted to build a discrete design. "Build an amp that can deliver a few watt into 8 Ω" is a common 3rd semester electrical engineering student assignment.

Tom
 
Use a TDA 2030A instead,or LM 1875, at 16V will give a lot more power - 3 watts. The minimum seems to be +/-8V, so 16V.

That is why I said use a circuit from a computer speaker, the TDA 2822 gives about 1Watt at 12 V per channel, and many audio chips are used in TV sets, sound bars, boom boxes and so on, in the 12V supply range.

And you may have some discarded computer speakers lying around, so you are simply using it for another purpose.

If you prefer, you get many ready populated circuit boards, in Classes AB and D...find them and use them.
 
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but do i really need that 50w of power and need to deal with the cooling for that chip
Write down your own specification for what you want.

What do you intend to drive with this amp?

A small chip like an LM386 will give the kind of output a small portable radio or TV would give. It can operate from a single rail battery supply if you wish or a single rail AC supply which makes it easy to use.
 
For my project, i'll use a small speaker, around 3W@4 omh or 8omh max. So a simple amp chip that sound good, forgiving in design layout will be enough. Currently, i'm looking at TI's chip selection and see some names like TPD3189D2 and TPA6030A4 :unsure:
Passive cooling, consume small amount of power (i'll run it from battery) and the simple in the design & layout is an important factor, since i don't want to mess with too many components at once.
I don't know whether i need 2 channels amp chip or just use 2 of it, or just use 1 channel, any recommend?
This is for a music box only, no hi-fi or whatsoever, the sound just need to be clean and loud enough for a person to hear.
 
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I don't know whether i need 2 channels amp chip or just use 2 of it, or just use 1 channel, any recommend?
You must decide and write down what you want (for your own use). Otherwise it is easy to get side-tracked.

For example the TPA6030A4, could be a good choice BUT are able to use it? Are you able to work with surface mount parts like these? Look at the data sheets, look how small the chip is, look how many closely spaced pins there are.

Are you hoping to design a board for these because there is no other way to use parts like those.

1 channel or 2?
If you want stereo you need 2, if you are driving a single speaker you do not.
 
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It looks like the venerable LM380 and LM384 are still available. These are about as simple as it gets. Otherwise, a trip to the TI web site lists several modern chip amps, some class-D and some AB.
https://www.ti.com/audio-ic/amplifiers/speaker-amplifiers/overview.html
But if you are going to the trouble of using a DAC, a better match would be a discrete amp since no chip amp is going to have audiophile performance. Perhaps an audio quality op-amp with a discrete 2EF output buffer.