428 Sigma-Delta ADC
428 : Sigma-Delta ADC
- Author: Martin Schoeberl
- Description: Analog to digital converter - and back
- GitHub repository
- View in Wokwi
- Clock: 50000000 Hz
How it works
Provide an analog signal at Vin (e.g., some music) and listen to the output at Vout (using an amplifier). The circuit will probably add some noise, as it is very crude. But it went from the analog domain to digital and then back.
Future work should be to use that sigma-delta coded signal to do some fun audio processing.
Anyone knowing how to do DSP in the sigma-delta domain?
How to test
Connect an analog source to your design and listen to the music (output).
External hardware
This is a sigma-delta AD converter and a DA converter.
The input is mixed with the feedback delay/inversion and uses the threshold of the DFF input as a comparator, serving as a single bit ADC.
The R and C values depend on the input signal and can be discussed and should be explored.
100k
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OUT0 o--|___|--+
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100k |
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Vin o--|___|--o----------o IN0 OUT1 o----|____|---o--------o Vout
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IO
| # | Input | Output | Bidirectional |
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| 0 | IN0 | OUT0 | |
| 1 | OUT1 | ||
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