Hello Dieter
once again me...
Am 19.11.2014 09:05, schrieb
yahoo@...
[Doepfer_a100]:
> A total different approach is to generate a CV from the rate of
> trigger signals coming from the quantizer A-156. For this kind of a
> frequency to voltage generator has to be patched, e.g. an A-162
> followed by a A-170 or A-171-2. The A-162 generates pulses with
> constant length which are integrated by a slew limiter (nothing but a
> 6dB low pass with very low frequency) to obtain a CV.
This approach has the disadvantage that the voltage always will drop
between two triggers. It will be like a sawtooth waveform; the lower the
trigger rate is the more the voltage will look like a sawtooth. And the
higher a change of rate is, the worse the slewlimiter will represent the
change of rates. I think the counter based approach is more exact and it
would not be that difficult to implement: simple CD4069 based clock
oscillator, two stacked 4bit downcounters (4526) to create the 8bit
value, and a resistor ladder D/A converter using buffers from the same
4069 as the clock oscillator, a TL062 as buffer, some resistors/caps around.
Florian