Oscillating TDA2822? why?

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I’m looking for a better sound, to me the lm386 sounded trebly, saturated way too quickly, and was not stable enough, with still less volume than I’d want.

Are there some class D chip Amp? Or am I looking at something completely different to implement? would you have some references? Chip names? I could look up? I definately have no problem about icing to class D, if that solves the problem.

Give a look to DIYBudgetAudio.com. There, some less costly alternatives are mentioned.
 
the PAM boards are 12v 2 amp for full rated output are you thinking of running this off a 9 v battery?

it would take 6 9v batteries in parallel to develop enough current to run for about one hour at full volume.

Yes that was the plan. The whole idea of going class D was to need less current, wasn't it?
If that's not the case, would you know an alternative? I don't need 10 watts, 1 or 2 would be ok, my constraint is the battery, not the decibels
 
Seems you've forgotten crest factor - if music is playing the worst case crest factor would be around 12dB. Meaning that the average power draw for a 15W peak amp would be of the order of 1W, assuming 100% efficiency.

I guess you meant 1A here? ok, but then how do these small battery powered amp work ? the small marshall MS2 uses the KIA 6213 chip, which I find hard to find (maybe i'm not looking at the good places).

Maybe i'm not looking at the right technology..
the idea is to have a small guitar amp
9v battery powered
0.5 to 2 watts into 8 ohms
doesn't sound too 'small' (LM386 sounds trebly, without bass)
doesn't saturate (LM386 clean headroom is very limited from my tests)
doesn't oscillate or ring easily (another issue with the LM386 in my tests)

which was the reason why i wanted to move on to chips like the TDA2822 or NJM2073, but i had no idea that the current needed would be so important (yes i checked the datasheets, but reading those and getting all the informations needed is apparently something that needs to be learned too :rolleyes:

So is there anything else better suited for my application?
 
No, I didn't mean 1A, I meant 1W. So around 100mA from 9V. That would be at full volume (subject to no clipping) for the lowest crest factor music. In practice the amp will be less than 100% efficient but also most music has a higher crest factor, these two tend to cancel each other out.
 
Not all 9V batteries are the same - obviously a PP3 isn't going to cut it, you'll need something which has an internal resistance low enough not to sag too much. Peak currents in audio are only called for for a few mS at a time, hopefully the decoupling capacitor can manage to provide for them. Average currents are much lower when the amp is classD compared to classAB.
 
No, I didn't mean 1A, I meant 1W. So around 100mA from 9V. That would be at full volume (subject to no clipping) for the lowest crest factor music. In practice the amp will be less than 100% efficient but also most music has a higher crest factor, these two tend to cancel each other out.


I'm sorry, i have never considered these factors before as i mainly tweak with preamps and effets.
I understand what the crest factor is, but what is the consequence of that?
The average power draw of the amp is much smaller than the peak ? So i would mean that it could be battery powered then ?
 
Yes the consequence of music's crest factor is that the average is at least 10X lower than the peak. With a classAB amp, the efficiency on music is fairly poor - much more energy is being wasted as heat in the amp's heatsink than in the voice coils of the speakers.

Your power requirements are very modest (2W peak) so unquestionably you can use a battery.
 
Yes the consequence of music's crest factor is that the average is at least 10X lower than the peak. With a classAB amp, the efficiency on music is fairly poor - much more energy is being wasted as heat in the amp's heatsink than in the voice coils of the speakers.

Your power requirements are very modest (2W peak) so unquestionably you can use a battery.

yay!
But then I need a chip that doesn't shut down every time i send some signal to it, like I just had with my tests with the TDA2822. How could i manage that? Lower the chip gain to have lower peak current needs? Another chip?
 
Based on the pictures you've shown, its quite likely that the shutting down you experienced was due to your sub-optimal implementation and wiring rather than being a fault of the chip itself. Getting a ready-built board with a chip on it should give the chip a better chance of performing up to spec. Don't skimp on the decoupling of the battery though!

Incidentally if you can order from Amazon there's an implementation of the same IC, PAM8610 here :Amazon.com: HiLetgo Mini Stereo AMP Audio Amplify Board Digital Portable Ampli Module 10W+10W Dual Channel Amplifier Class-D 12V DC: Electronics
 
Based on the pictures you've shown, its quite likely that the shutting down you experienced was due to your sub-optimal implementation and wiring rather than being a fault of the chip itself. Getting a ready-built board with a chip on it should give the chip a better chance of performing up to spec. Don't skimp on the decoupling of the battery though!

Incidentally if you can order from Amazon there's an implementation of the same IC, PAM8610 here :Amazon.com: HiLetgo Mini Stereo AMP Audio Amplify Board Digital Portable Ampli Module 10W+10W Dual Channel Amplifier Class-D 12V DC: Electronics

thanks, i already have some PAM boards on the way :D

So maybe using the TDA2822, with a perfboard or a small pcb instead of a creappy breadboard would solve the shutdown problem?
I'll definately try that.
Could a breadboard implementation also create distortion?
 
So maybe using the TDA2822, with a perfboard or a small pcb instead of a creappy breadboard would solve the shutdown problem?
I'll definately try that.

You could answer that question fairly speedily if you order up one of these : TDA2822M?4???(??????/MINI?????)-??-???

Could a breadboard implementation also create distortion?

Certainly because once you have oscillation, distortion comes for free :D
 
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