parallel, slaved TDA7293 kits - any out there?

[CharlieLaub]

I am very interested in obtaining/building an amp that uses two TDA7293 chip amps in parallel, using the slave feature to join the output stages. Unfortunately I don't have any experience in PCB development or I would try to go it alone.

Has anyone out there successfully developed a PCB or kit along these lines?

TIA,

-Charlie

[CharlieLaub]

Are there really no kits using this feature? I would think that people would jump at the opportunity to have two chips's worth of gain stage. The app note in the datasheet says that for "slave mode" you don't need the balancing resistors on the outputs like you do with other chip amps (e.g. LM3886) when using two in parallel, and this seems to be a significant advantage, since the power output is comparable to the LM3886.

Any thought on this at least?

-Charlie

[abraxalito]

Its a three-chip parallel design, so maybe you could just omit one...

Quekky TDA7293 amp

Yep, I agree its a very nice feature of the chip to be able to parallel it so easily.

[linuxguru]

There are plenty of parallel 7293/94 boards on EBay - like this one:

TA7293 x4 BTL + parallel 350W 4 ohm amplifier PCB - eBay (item 220412063073 end time Mar-06-10 05:52:27 PST)

Edit: The solder-side image does not correspond to the component-side image in this listing - this design probably doesn't use a star ground, and instead has a ground plane. It might be susceptible to ground bounce. However, there are several other designs on EBay - just take your pick.

[CharlieLaub]

Originally Posted by linuxguru

There are plenty of parallel 7293/94 boards on EBay - like this one:

TA7293 x4 BTL + parallel 350W 4 ohm amplifier PCB - eBay (item 220412063073 end time Mar-06-10 05:52:27 PST)

Edit: The solder-side image does not correspond to the component-side image in this listing - this design probably doesn't use a star ground, and instead has a ground plane. It might be susceptible to ground bounce. However, there are several other designs on EBay - just take your pick.

I specifically am looking for parallel 7293 amp boards that use the slave feature of the chip. All the Ebay boards have adapted the typical paralleling circuit used for the LM3886, etc. that need load balancing resistors on the chip outputs. Also, I don't need 4 chips in a series-parallel connection since I need the output to return to ground. The 4 chip boards have no ground connection.


If you happen to find am amp board on Ebay that uses a SLAVED 7293, please let me know.

Thanks

-Charlie

[CharlieLaub]

In case there are other people reading this thread who want to locate this type of amp, I did find a company in the USA who is selling PC boards to implement two TDA7293 chip amps in parallel with the second chip slaved to the first:
James Audio: Products

Scroll down about 1/2 way to see the chip amps (the mono version is the one I am referring to). There is also a schematic. They are selling PC boards with a parts list and instructions.

I am not sure why there are not more kits like this out there... except perhaps that the datasheet evidently had some errors regarding the slave connection component values, etc. and this might have led to some disasters by DIYers trying to implement that configuration.

-Charlie

[Minion]

I believe part of the reason why they don"t use the Slaved configuration is because without it you have the option of useing the board as a stereo board or as a Paralell mono board or even a Bridged board .... There are also a few old threads here about poeple haveing problems implementing the Slaved function but Can"t recall the exact problems they had ....

Cheers