# PSU for TPA3118 Power Amp



## Elijah-Baley (May 13, 2020)

Hello guys.
I built some mini amp, a pair based on the LM386 and one with the TDA7052.
I've been stuck for a long time with a TDA2003. I wanted to do something great with two channel preamp, boost... a long story.
I would like to buy a TPA3118 Power Amp board now, but my main problem with this bigger power amp is the PSU. I use a old Boss 9v 200mA for my pedal, but for this power amp it's not good.
I bought some years ago a RockPower PSU 18v 2A. I tried just one time with a Vemuram Jan Ray DIY, but it was noisier than my Boss PSU, and I never used it, anymore.
To build a PSU it's not so good for me, something like that often costs more and need more space than something we can to buy. And I am a guy who prefer to build for fun instead to buy.

So, where I can find a psu to use the TPA3118 Power Amp (and the TDA2003)?
To reach the right voltage I can use charge pump and regulator of course.
Someone uses laptop's psu, but I read that sometime those kind of PSU are too noisy to use with audio devices. I have just one PSU of my old netbook, but the plug is a small type, so I never tried it.

Thanks.


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## temol (May 13, 2020)

You need a PSU that can give you 1A to 2.5A, depending on the type of the power amp. Because of this you cannot use any of the poplular charge pumps we usually use. Traditional power supply would be big and heavy (transformer). I'd search for good quality switched power supply.


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## Elijah-Baley (May 13, 2020)

This is the point. I really don't know what power supply I need for these amps.


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## Willybomb (May 13, 2020)

You can grab a second hand laptop power supply for minimal dollars from the junk box at most computer shops.  Grab one that puts out around 30v @3a or so, and cut the jack off so you can hook the wires up to whatever you want.  I have a 3116 or something like that, that I was experimenting with.  I found it noisy with the laptop supply but I'm sure I can filter it or something.  You won't loose anything by giving it a go.


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## Elijah-Baley (May 14, 2020)

For me it isn't so easy buy some used stuff. I hope I can find something, asking around, or in some shop.
About the noise, the thing can be a problem. Someone told me that a filter in the output of the PSU (on our circuit board) is almost useless if there's no filter in the input of the PSU, I mean right inside the PSU.
A laptop PSU is ok about voltage and current draw, but it's for laptop, not audio device. To find a noiseless PSU, cheap or expensive, it's a lucky shot. With a noisy PSU we can't supply our amps and pedals.


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## stevel (Jun 17, 2020)

I bought a 24V 4A power supply on Amazon.

Click here to see power supply

This power supply is intended for printers according to the advertisement, but that is irrelevant. It works well with both of the amps I built (TPA3118, and TPA3116) and it is quiet.

BUT (and this is a big but)....

This power supply comes configured for center positive. So when you build your amp, you need to make sure that you configure the DC jack for center positive. The other option is to make or buy a polarity reversing cable, and setup your amp with a center negative DC jack (that is what I did because all of my power supplies are center negative).


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## Elijah-Baley (Jun 18, 2020)

Thank you.
I'm from Italy, it's a bit hard to find exactly the same PSU you got. I hope some PSU for the same device will be good.
I tried a 12v with center positive once, and I reversed 9v and ground wire on the DC jack of that circuit I want to try. I think there's no problem with it, because I'll use, in case, that PSU just with this amp.


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## Elijah-Baley (Jan 1, 2022)

I want to bump this my topic (that I forgot) because this year I would like to buy a TPA3118, but I afraid to buy any PSU.
So, if the PSU you used work fine without any noise or issue and I can buy it on amazon or ebay in EU, I'll be glad if you suggest the model.

Thanks!


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## Willybomb (Jan 1, 2022)

The laptop ones work fine in my further experience.


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## Elijah-Baley (Jan 2, 2022)

A laptop one fore sure, I'm afraid to buy one and found it noisy, I wrote it everywhere. 
I got some suggestion, but I can't to buy exactly the same model in the shop available in my Country.


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## Willybomb (Jan 2, 2022)

Did you try putting a 4700uf across the +ve and -ve power?


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## Elijah-Baley (Jan 3, 2022)

I still have to buy the TPA3118 PCB, and the PSU. But if that's enough to solve noise issue I have a pair of big 4700uF.
So, in case I could add a sort of noise filter with a 1N5817 in line, a big electrolytic cap and maybe a smaller ceramic cap.
By the way, I'll buy, I have to decide where, that blue one PCB, I think it's all the same the blue one, right? But, is there the schematic of that PCB?


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## Willybomb (Jan 3, 2022)

Datasheets are here.  They might have a generic schematic for using them: https://www.ti.com/product/TPA3118D2

You want the mono version of the little blue one (google: 60w mono TPA3118d2) or the mono version of the TPA3116D2 (google 100w mono tpa3116d2).  Both work equally well.


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## Elijah-Baley (Jan 3, 2022)

These are the PCB board I can find:








						TPA3118 BTL 60W Mono Digitale Audio Power Scheda di amplificazione Modulo DC ...  | eBay
					

Le migliori offerte per TPA3118 BTL 60W Mono Digitale Audio Power Scheda di amplificazione Modulo DC ... sono su eBay ✓ Confronta prezzi e caratteristiche di prodotti nuovi e usati ✓ Molti articoli con consegna gratis!



					www.ebay.it
				











						TPA3118 Mono Power Amp Module
					






					www.op-electronics.com
				



Amazon or AliExpress, too.
There are a lot of of these blue board, I think those are all the same board.
It's very simple: One Input, One Output (I guess bridged, mono, anyway), the Mure, the Power.
In case I would like to see the schematic of this particular board, but probably it's not necessary if I have just to add caps in as power filter. I guess I don't need to do something more.


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## fig (Jan 3, 2022)

I did one. That's really all you need to do. 






						Practice Amp
					

This is not recent, but I've mentioned it a few times...  It's a "Tube Screaming Preamp (B. Robertson)" into a "100 watt" one-channel power amp. From my understanding, these are used a lot to power car subwoofers and such. Being that it is a only power amp there are no external controls, it is...




					forum.pedalpcb.com


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## Elijah-Baley (Jan 4, 2022)

Your built it's very nice.
I prefer to use the smaller 60w version, but... you used a battery? I think a PSU it will be ok for me.


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## fig (Jan 4, 2022)

Yes, they work well with a PSU. I powered it that way when I was near to an outlet.


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## Elijah-Baley (Jan 5, 2022)

I'm searching a laptop PSU to buy, at least 19v and 3A, I'm not sure if I have to use 24v, because that is close to the limit for the TPA3118.
Do you have a brand or model in particular. Did you have pictures of your PSU used with this kind of power amp?


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## Willybomb (Jan 5, 2022)

I literally walked around the secondhand shops looking at the back of the power supplies until I found one with the required specs written on the back.  Most of mine are 19v@~3.5 except for the new ones that are 24v@5a.  Those are bigger than the enclosures I'm putting the amps into.

Seriously, it doesn't matter.  Just make sure it's wired for the correct polarity (you'll probably have to replace the jack).


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## Elijah-Baley (Jan 5, 2022)

I hope I'll not have noise issue with a PSU I'll buy then.


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