[help] What kinda circuit can i build to power 3 Amplfiers?

Shiroou

Member
2015-12-29 10:12 pm
Very well , i recently got a ( burned ) home theater from a friend .... yet the speakers are fine. They are rated to five watts ( 6x5w ) ... so I thought ...
Would I capable to hook up 3x TEA2025 from STMicroelectronics and create a multi channel sound system?
Well i did it and it is Working just fine, but i'm facing a problem... How to power 3xTEA2025 + 1xTDA2030 for a woofer...

So on this context what kind of PSU should be used? and how can a create a circuit to power all 4 amplifiers?
 

Jay

Banned
2003-02-11 9:02 am
Jakarta
TEA2025 is less than 2W and maximum supply is 15V. So you don't need high voltage for the TDA2030. You can supply TDA2030 with the same supply, i.e. 15V to get around 14W (depends on speaker impedance).

You can use the same power supply as you are using now, except that now you need a bigger transformer. If the transformer is big enough, you can try to power all amps from that supply and see if it is sufficient (not heated up, enough power). If you need more power, you need separate transformer, can be with bigger voltage, and the circuit is similar (the simplest form: 2 or 4 diodes plus 1 capacitor).
 

Jay

Banned
2003-02-11 9:02 am
Jakarta
It may look like a basic stuff but IMO it is an advance topic...

Sharing the PSU between the amps might not the issue. In the home theater there may be digital circuits. They are sources of HF noises. If they share the same PSU with the amp, you have issue (CLC isolation may be needed).

Regarding the amps, I believe it is LF issue (a.k.a hum)? You need good grounding, layout and bypassing. Regulation for the TEA might help but I think chip amps have already sufficient PSRR.

More capacitance will help. Local bypass will help. Proper grounding for sure (this is the difficult part). Short PS cable, twisted.