PCM1794A board maximum analog supply voltage?

Hi all,

I have one of these nice DAC boards:
Unbenannt.jpg

They say the analog supply voltage shall be +-12V. But AFAIK, the PCM1794A only sees the digital 5V supply voltage, while the maximum analog voltage is mainly determined by the op amps. So, if I'm using NE5532/34 op amps, +-17V should be safe.

Can anyone confirm this?

Thank you!
 
Yes, it's working nicely.

If I remember correctly, the 5V supply for the DAC chips is powered by the +12V input. So, the 12V supply cannot be raised to 17V without the risk of destroying the regs.
Therefore, I simply removed the 5V regs and connected the 5V input voltage directly to the former output pin of these regs. With this mod, I could increase the +-12V to +-17V.

I did not do this for sound reasons, and I do not think it makes a big effect. But I didn't do measurements. The modding was done for easier integration into my setup.

Cheers!
 
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Thank you. I've ordered one without the opamps as I plan to use my Sowter I/V transformers which are designed for balanced dacs.

According to the listing, there's one dac for each channel. I assume they are set for L and R with the Mono, CHSL, FMT0 and FMT1 pins suitable configured?

This means I won't need the 12v input if the 3.3v is derived from the 5v connection.

I am using it to replace (maybe only temperorarily!) the audio board in a recently acquired VRDS10. This uses a par of TDA1547/ DAC7 bitstream dacs and conveniently, the digital data signals and psu conenctions are via 0.1" pins. It receives two separate AC supplies, each regulated to +- 12 & +-5v respectively with 7805/7905/7812/7912 regs.

Either way, I can make my own low noise supplies from these two AC rails.