4) Can I try circuit for few seconds/minutes on breadboard (signed max 2A), using 9V or 12V battery?
Corrected thanks to AnalogKid and Audioguru, 2016_11_02
Hi PN,
Have no fear, you can use the TDA2005 amplifier on a 2A rated breadboard for as long as you like; audio amplifiers do not take much current when reproducing music.
Besides, assuming that you have a 12V battery and a 4 Ohm speaker, the peak current would be, 6V/4 Ohms = 1.5A (in fact 6V should read 5V because the TDA2005 output does not swing to the supply rails) and the average current of a sine wave (audio signals comprise sine waves) is 0.707 * peak current. So the average current with a 4 Ohm speaker will only be 0.707 * 1.5A = 1.06A. But the VCC and 0V pins supply the current for both amplifiers on the TDA2005, so in theory the current could be 1.06A * 2 = 2.12A, but the chances of this current being generated with music is slight and the odd peaks of current now and then is not likely to damage the breadboard. You could always link adjacent breadboard pins together to supply the OV and VCC pins if you like.
Also, the 2A breadboard rating will apply to each socket on the bread board not the whole breadboard. But if you passed 2A through all 75, or so, sockets on the breadboard, the breadboard would overheat.
While I fully agree with the other members points about the undesirability of building the TDA2005 amplifier on a breadboard, for the reasons stated, you should be able to get the amplifier working on a breadboard, especially if you use a decent layout, adequate decoupling, and a solid power supply.
The TDA2005 has built-in thermal and current protection and, apart from gross abuse (like connecting the supply lines the wrong way around), you are unlikely to damage the TDA2005.
An old trick when testing power circuits for the first time is to put a current limiting device in the circuit until the circuit is built and tested satisfactorily. In this case, a resistor of around 10 Ohms (3W or more) in series with the speaker would be a good safety precaution. Another safety precaution would be to put a 1 amp fuse in series with the positive supply line (before the supply line decoupling capacitor).
In addition to quickly draining a small 9V battery (PP3), as has been said, PP3 batteries also have a relatively high output resistance (ESR), which increases rapidly as the battery discharges. A relatively small resistance in the supply line can cause the amplifier to be unstable. Also, PP3 batteries are troublesome little things and are really only suitable for light loads. A 1,000uF or greater capacitor across the supply line will help, but you really need a solid supply line.
One of the reasons for needing a good supply line is that, (unlike class A amplifiers, where the supply current drain is constant), class AB amplifiers (like the TDA2005) take relatively large gulps of current from the supply line. Thus, not only will a poor supply tend to cause frequency instability, but it will also generate distortion in the output audio signal.
As to the error on the schematic of the output capacitor being shown the wrong way around: errors are a fact of life. There is a temptation to think that just because information appears in print, especially in books, and on the internet that it is correct. Nothing could be further from the truth, especially on the net. One of the major aspects of engineering is to be able to check for, and handle errors- which is what you have done in this case.
There is nothing more to errors than... er just errors. There are very few areas where, if examined in detail, you won't find errors. You may even find an error in this pist.
You can make quite a nice amplifier, easily and cheaply, using a single-chip approach. I have built and repaired quite a few along the way.
spec
PS: where are you from? If you put it next to 'Location' on your user page it will display in the box at the left of your posts.
DATASHEET
https://www.st.com/content/ccc/reso...df/jcr:content/translations/en.CD00000124.pdf