TDA2003 amp

[e44-72]

Hello

I was planning on making this amplefier circuit giving a mono output for one speaker using a TDA2003 power amp. I have a few questions.

If i have the inputs wired to a mono jack socket, (probably 3.5mm) would this circuit be able to amplefy the output from an insrtument such as an electric piano?
Would the amp work on a power supply from a 9v battery or would it need to come from dc tranformed mains power?
I also don't know why the non inverting input come from the positive of the 10 uf cap, should this be the other way round so the positive of the cap is coneected to the input from the jack?
Last one which is more practical, would this package (t0220) be mountable on stripvboard, on the data sheet pins seem to close but could they be bent to fit. If not can any suggest an alternative dil package that would fit and work in place?

Datasheet and circuit are attached, thank you for your time and help.

 

[audioguru]

I was planning on making this amplifier circuit giving a mono output for one speaker using a TDA2003 power amp. I have a few questions.

If I have the inputs wired to a mono jack socket, (probably 3.5mm) would this circuit be able to amplefy the output from an insrtument such as an electric piano?

Yes.

Would the amp work on a power supply from a 9v battery or would it need to come from dc tranformed mains power?

It is designed for a 14.4V supply from a charging car battery. With a supply as low as only 9V then its output power is only about 0.8W into 8 ohms. But a little 9V battery voltage drops as it is used so the output power will soon be less than 0.5W.

I also don't know why the non inverting input come from the positive of the 10 uf cap, should this be the other way round so the positive of the cap is coneected to the input from the jack?

No. The schematic shows the correct polarity of the capacitors. The IC has positive voltages on its terminals and the input volume control is connected to 0V.

...would this package (TO220) be mountable on stripboard, on the data sheet pins seem to close but could they be bent to fit. If not can any suggest an alternative dil package that would fit and work in place?

An LM386 amplifier IC has an output of 0.45W into 8 ohms with a 9V supply. It is in an 8-pins DIL package.

 

[e44-72]

Thanks you very much for your help and answering all of much questions. Thank you for your time

 

[bountyhunter]

The TDA2003 and TDA 2002 have internal bias to set the output at about 7V, since the nominal design rail is 14V (car system). It won't work worth beans with a 9V supply since the output will have no room to swing.

 

[e44-72]

Thanks you for your reply, if I used a 12v dc supply from a plug in transformer that tranforms it to 12v from the 240v mains would that work better. I also wanted to know whether a sink would be needed if I used the lm386.

 

[e44-72]

Hi again, just had a look at lm386 pinout, what do the gain and bypass pins do and will they be needed to be conneted to anything (tied to +ve or ground), thanks again

 

[audioguru]

Thanks you for your reply, if I used a 12v dc supply from a plug in transformer that tranforms it to 12v from the 240v mains would that work better?

A transformer has an aC output that needs a rectifier and filter capacitore to make DC for the amplifier. You need an AC-DC power supply instead.
The TDA2003 works well with a 12V to 15v DC supply but its power into an 8 ohm speaker is almost half as much as with a 4 ohm speaker.

I also wanted to know whether a sink would be needed if I used the lm386.

Its datasheet shows that with a 9V supply its power into an 8 ohm speaker is only 450mW and then its heating is only about 400mW which is fine. Its case cannot use a heatsink because it is a low power amplifier.
If you increase its power supply voltage then the max output power is almost the same but its heating is much more which will destroy it. It is shown on the datasheet that you did not look at.