[sdiy] Doepfer Sound Sampler / Elektor Quantizer

[Louis van Dompselaar]

Op 23 jun 2009, om 16:29 heeft Rainer Buchty het volgende geschreven:

> Since it's just an 8-bit R2R-based DAC, shouldn't a manually wired R2R
> network e.g. using measurement resistors (0,1% tolerance) be a  
> suitable
> substitute?

It might, although the circuit actually uses a sliding reference voltage
to achieve dynamics, so it's not a trivial replacement.  The way the ZN
switches the ref voltage would probably need to be incorporated.  Just
putting in the R-2R ladder on the data bus would lose the dynamics as
a "1" would then always be 5V, instead of the reference voltage.

It might be easier to find a replacement among the readily availble
DACs.  The PCB would need to be redesigned anyway, as it's probably
far cheaper to use one large SRAM instead of 16 6116s.