[sdiy] Fun with an ht8950 voice processor

[Eric Brombaugh]

Paul Perry wrote:
> If it is possible to run the Holtek chips - especially the delay chips 
> - in
> direct-coupled circuits, it would be possible to make very interesting CV
> processors from them.
> All the application note circuits have capacitor coupled input & outputs,
> but that doesn't mean it is impossible.

Looking at the datasheet, it appears that the input of the ht8950 goes
into an op-amp with a VDD/2 reference available on a pin. You could use
that to set up the input DC bias to eliminate the blocking cap. If
you're lucky then the output D/A runs off the same reference as the A/D
so the output offset would be identical.

Like the description "The 8-bit A/D and D/A converters with a sampling
rate of 8kHz ensures a high quality and high S/N ratio output." :)

Eric