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TDA2822M Amplifier Audio Output is Cracking, Please Help !

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With R1 removed then there is noise?? R1 has nothing to do with noise.
Please describe the noise. Hiss? Feedback squeal? Hum?

EDIT:
Do Not use an IC socket and Do Not use a breadboard because the little IC was designed to dissipate its heat through its pins to the copper on a pcb.
 
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EDIT:
Do Not use an IC socket and Do Not use a breadboard because the little IC was designed to dissipate its heat through its pins to the copper on a pcb.

Heat is not an issue under 6V power supply, Don't you see lots of kits made using the same IC and they all use IC sockets? Below kit from 'google' use 9V supply.

**broken link removed**
 
Heat is not an issue under 6V power supply
Correct. But they use 8 ohm speakers. This guy is using 4 ohm speakers so the heating is much more.

Don't you see lots of kits made using the same IC and they all use IC sockets?
Many kit manufacturers do not read datasheets.
The ground pin #4 is shown to carry away heat much better than the package can. Why overheat the IC?
 
Is this amp on a bread board?
What do you have hooked up to the input??
What kind of speakers are you using???
 
@ transistor495, ronv, audioguru & 4pyros

Thank you so much for helping me out till now.
I know this is a very simple circuit, making it was really simple but as a n00b fixing it is quite challenging

@audioguru
the noise was hiss...

@4pyros
no, it's on a matrix board
i use the circuit for both my music player & laptop (3.5mm out)
i'm currently using two 4ohm/1w speakers & planning to replace them with two 8ohm...

@all

due to lot of changes to the circuit recently, the solderings are now a bit messed up.
I'm thinking of making a circuit from scratch as now it seems pointless fixing the old one.

can anybody please help me out with a good tda2822m amplifier circuit

few details :
i want to use two 8ohm Speaker
power supply from usb or batt.
good quality music with decent bass

I'm sorry if anything above was wrong, I don't know much about them so please notify me if there's any...
 
can anybody please help me out with a good tda2822m amplifier circuit
It is shown on the datasheet.

I want to use two 8ohm Speakers
Then the output power at clipping per channel will be only 0.135W with a 5V supply. VERY low power.

good quality music with decent bass
Fairly large SPEAKERs in enclosures designed properly make good bass.
 
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good quality music with decent bass
You will not get "good" bass with small speakers running of 5 volts.
i want to use two 8ohm Speaker
For 5 volt operatoin you would be better off with 4 ohm speakers.

You can't have your cake and eat it to!
 
The TDA2822M amplifier IC is shown on its datasheet to produce 0.9W with fairly low distortion into 8 ohms with a 6V supply when both of its amplifiers are bridged.
 
You will not get "good" bass with small speakers running of 5 volts.

For 5 volt operatoin you would be better off with 4 ohm speakers.

You can't have your cake and eat it to!

i'm not asking for hq bass
i just want that the music doesn't sound metallic
bass equivalent to ~160hz will be enough

The TDA2822M amplifier IC is shown on its datasheet to produce 0.9W with fairly low distortion into 8 ohms with a 6V supply when both of its amplifiers are bridged.

if i use "Test Circuit (Bridge)" from the datasheet, is it possible to make the stereo channel (from music player & laptop) mono, so that i can hear both the channel from the same speaker

i have a 50kohm stereo volume control, how can i implement it in the "Test Circuits" from the datasheet replacing the 10k resistors

Will it work from usb power supply
 
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i'm not asking for hq bass
i just want that the music doesn't sound metallic
bass equivalent to ~160hz will be enough
160 Hz is "telephone quality" (female voices with no bass). You can hear 1 octave lower to 80Hz, hear another octave lower to 40Hz and hear another octave lower to 20Hz. But most speakers do not go below 30Hz.

if i use "Test Circuit (Bridge)" from the datasheet, is it possible to make the stereo channel (from music player & laptop) mono, so that i can hear both the channel from the same speaker
Two series resistors (one from each channel) make a stereo to mono mixer circuit.

i have a 50kohm stereo volume control, how can i implement it in the "Test Circuits" from the datasheet replacing the 10k resistors
Your 50k volume controls will the 10k resistors but their higher resistance creates some hiss noise.

Will it work from usb power supply
It will work but the output power will be VERY low.
 
Just a thought - have you tried this with headphones? I think everyone else has covered this well so far - a good clean power supply (try using a 7805 regulator powered by 9V to simulate your USB, it'll have lower noise) - then try a new amplifier chip, and finally, a set of headphones/earphones of which you know the impedance.
 
@audioguru

I built the bridge test circuit from tda2822 datasheet
as per your suggetion & some ideas from previous circuit i made the input circuit (stereo to mono mixer with volume control) like this :
View attachment 68821

so far it's working fine for my laptop but if i connect to my music player the sound is low & increasing the volume using the 50k increases the volume with simultaneous increase in distortion

should i eliminate the 10k from the amp circuit or reduce the series mixer resistances

any suggestions ?

@Blueteeth

Thanks for your suggestion, but i discarded the previous circuit due to some mess up & built a new one as you can see from above.

any suggestions ?
 
Your mixer has two 47k resistors feeding the 50k volume control, the 10k amplifier input resistor and the 100k IC input resistance that makes an attenuator reducing the input to 0.16 times.

If you replace the 10k amplifier input resistor with a 10k audio taper volume control, replace the two 47k resistors with 4.7k and increase the value of the capacitor (for good bass) then the attenuation is only 0.52 times.
The amplifier has a gain of 100 that is plenty.

I think your amplifier is oscillating at a high frequency when you turn up the volume control. The oscillation causes distortion, heats the IC and drains the battery quickly. Keep the volume control wires away from the speaker wires.
It might oscillate when built on a matrix board, use a compact pcb layout or stripboard instead. A recommended pcb layout is shown in the datasheet.
 
Your mixer has two 47k resistors feeding the 50k volume control, the 10k amplifier input resistor and the 100k IC input resistance that makes an attenuator reducing the input to 0.16 times.

If you replace the 10k amplifier input resistor with a 10k audio taper volume control, replace the two 47k resistors with 4.7k and increase the value of the capacitor (for good bass) then the attenuation is only 0.52 times.
The amplifier has a gain of 100 that is plenty.

I think your amplifier is oscillating at a high frequency when you turn up the volume control. The oscillation causes distortion, heats the IC and drains the battery quickly. Keep the volume control wires away from the speaker wires.
It might oscillate when built on a matrix board, use a compact pcb layout or stripboard instead. A recommended pcb layout is shown in the datasheet.

absolutely correct, the ic is becoming hot as soon as the volume is increased
for info,
i'm using an 8ohm 1.5w speaker
usb power supply
stripboard for the circuit

i used ceramic capacitors for the two 100nf & one 10nf in the bridge circuit, is it necessary to replace them with film capacitors as well ?

Edit :
just for knowledge, what's the benefit of using film capacitor instead of ceramic
 
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i'm using an 8ohm 1.5w speaker
Good.

usb power supply
stripboard for the circuit
Good.

i used ceramic capacitors for the two 100nf & one 10nf in the bridge circuit, is it necessary to replace them with film capacitors as well ?
Ceramic works best at stopping high frequency oscillation.

just for knowledge, what's the benefit of using film capacitor instead of ceramic
A ceramic capacitor changes its capacitance when its voltage is changed. Then the signal changes its capacitance which distorts low frequencies. A film capacitor does not cause distortion.
 
@audioguru
Thanks for all the valuable info !

So,
Should I replace all the ceramic capacitors I used in the bridge circuit with film type or just the 330nf as you suggested is necessary to be film type ?
 
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Should I replace all the ceramic capacitors I used in the bridge circuit with film type or just the 330nf as you suggested is necessary to be film type ?
The ceramic 100nF and 10nF capacitors reduce high frequency oscillation and should be ceramic which is good at high frequencies.
But the 330nF film capacitor PASSES audio. A ceramic capacitor passing audio causes distortion.
 
extremely sorry,
my circuit is not exactly as in the datasheet.
rather it's like this :
View attachment 68835

I think the only diff. in this circuit is that the 10uf(C3 in datasheet circuit) is being used for passing audio (C5 in this circuit) but now i'm really confused on how to connect your mixer + volume control circuit with it.
can you please guide me..


Some questions though,

1. why in the datasheet circuit there is a 10uf caps between vcc & gnd ?
2. will it be better to shift the 10uf C5 in this circuit to vcc & gnd (as in the datasheet circuit) ?
3. is the 10uf c5 (i used electrolytic cap.) in this circuit plays the same role as the 330nf in your mixer + volume control circuit ?
4. will the 10uf electrolytic be better than the 330nf film for passing audio ?

Thanks!

I apologize for this noobish behaviour !
 
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330nf isn't available here, will 474nf do the job ?
330nF is 0.33uF which is marked "334" in Asia. It should be available anywhere.
An Asian "474" capacitor is 470nF or 0.47uF and can be used instead.

my circuit is not exactly as in the datasheet.
I think the only diff. in this circuit is that the 10uf(C3 in datasheet circuit) is being used for passing audio (C5 in this circuit)
C3 in the datasheet is a very importannt Supply Bypass Capacitor that keeps the IC from oscillating. It DOES NOT PASS AUDIO.
Your circuit has it missing.
C5 in your circuit passes audio to the input of the amplifier and since your input resistor is 10k then the capacitor should be a film capacitor of about 330nF or 0.33uF or an Asian 334 greencap. An Asian 474 will also be fine.

i'm really confused on how to connect your mixer + volume control circuit with it.
The The two 4.7k mixer resistors and 330nF coupling capacitor connect to your 10k audio taper volume control.

1. why in the datasheet circuit there is a 10uf caps between vcc & gnd ?
All electronic circuits need a supply bypass capacitor that keeps the supply voltage from jumping up and down when the circuit uses current. It prevents an amplifier from oscillating.

2. will it be better to shift the 10uf C5 in this circuit to vcc & gnd (as in the datasheet circuit) ?
10uF as an input coupling capacitor is way too much. it should be a 330nF film cap as I said before.
The 10uF capacitor can be used as the supply bypass capacitor.

3. is the 10uf c5 (i used electrolytic cap.) in this circuit plays the same role as the 330nf in your mixer + volume control circuit ?
Yes. 10uF is way too high. It can pass earthquake vibrations.

4. will the 10uf electrolytic be better than the 330nf film for passing audio ?
Its value is 30 times too high so it can pass frequencies as low as earthquake vibrations (1.8Hz). Audio goes only as low as 20Hz and the 330nF capacitor produces a 53Hz cutoff frequency into the 10k volume control parallel with the 100k input resistance of the IC which is fine.

If you use a 20k ohm volume control the the 330nF input coupling capacitor can produce a cutoff frequency of 29Hz.
 
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