Looking to make a small amplifierHowdy all,

Thread Starter

poolman966554

Joined Jan 22, 2014
38
Howdy all! A few years back i bought a small amp to power a couple speakers (Lepia lp-808). i finally got around to it, and while in testing, i realize its not very loud.. i was considering making my own amp after i was browsing mouser and come across a TDA7396. its 12vdc friendly, and appears to be the most simple circuit ever lol.


I see its mono input/output, maybe i should be looking into a left/right input ic?? The amp input signal will solely be a phone via 3.5mm jack.

datasheet:
http://www.mouser.com/ds/2/389/tda7396-957244.pdf


Questions:
1) is this circuit really that easy to construct??
2) can i omit pins 4 and 8 as i dont wanna bother with the extra functions?
3) is there a better option out there; i.e 12v compatible, 40ish watts rms
4) suggestions on a 2 channel input??

I just happen to find this IC in a few min of searching, and am considering it. I see its 4 years old, not sure if its been surpassed immensely for what it does.

Advise is much appreciated!
 
Last edited:

crutschow

Joined Mar 14, 2008
25,256
1) is this circuit really that easy to construct??
If you are careful about layout and decoupling.
2) can i omit pins 4 and 8 as i dont wanna bother with the extra functions?
Yes, but I would pull pin 4 high through that resistor to the supply voltage.
3) is there a better option out there; i.e 12v compatible, 40ish watts rms
Don't know of any offhand.
But note that the 45W rating is for a 2Ω speaker.
It will only generate 22.5W into a more typical 4Ω or or 11.25W into an 8Ω speaker.
That's a limit determined by the 12V supply voltage, not the amp.
4) suggestions on a 2 channel input??
Buy two.
 

Thread Starter

poolman966554

Joined Jan 22, 2014
38
Sweet! Thanks for the response and the heads up on pin 4! I suppose building a dual chip circuit wouldn't be that hard at all considering the simplicity!

Btw, I have 6.5 coaxial that are 2 ohms. So that works out! Was originally planning on running them in series to get 4ohm..
 

Thread Starter

poolman966554

Joined Jan 22, 2014
38
ok, so i finally had time to design the pcb, but before i proceed to etch board , is there a "gain" or volume function i might regret not adding??

The Lepia 808 i mentioned above does have a volume knob. is it just a pot on the input? or is there another place in the tda7396 circuit one would install a pot?

I put a scope on the lepia and it only made 0.4watts clean on a 80 hz sine wave. It made 7 watts on full volume square wave :(
hoping to achieve greater performance out of this chip.
 
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