just had a look at the datasheet - apparently the sensitivity can be adjusted, by balancing R1 and R2.
i would think these resistors could easily be replaced by a simple trimmer, to find the sweet spot for 3v3 operation?
maximum difference between 3v3 and 5v operation seems to be an 11ms increase in response time.
but maybe that's cricital, don't know what you're working on..
greetings from a quiet antwerp 
Hello, London (?) and Antwerp (cool!),
The reason why I'm asking is this:
5 volt makes the detection distance significantly larger. But indeed it's VDD that needs this! From one of the spec sheets (I realize now - 
- 
)
Figure 3 shows the relationship between detection distance and sensor size. Higher V DD voltage also extends the distance, because with higher V DD the sensor will generate stronger electric field for sensing.
@giuliomoro Where is
P9.07 ?
Here?
I'm trying with the potentiometer, but the sweet spot of activation is just so much further from the sensor with 5 Volt (which I now understand and did not before).
Thanks so much for thinking and reading along with me! First time I've used a smd sensor from scratch 
Greetings from Brussels, where at this hour 'there ain't nobody here but us pigeons',
Delving deeper into the electronics universe..
Ciaooo - keep safe - 
W
hah. that graph makes sense. funny enough, it doesn't seem to show in the datasheet that was linked above.
well, best to follow giuliomoro's advice (and the datasheet).. run the whole thing on 5v, except the pullup on the bela digital pin which should be 3.3v.
i'm SO repeating what has already been said, haha
Remork Perfect - confirming repetition is good 
This chip has a whole boatload of spec sheets.. https://www.microchip.com/wwwproducts/en/MTCH101
Bedankt!
giuliomoro An interesting application mentioned in the datasheet is that if you need programmable trimming of the voltage into MTSA, you could use one of Bela's analog outs instead of a resistor divider.
I know, it's with PWM, I believe. I chose the voltage dividers, because I have to figure out PWM with Pure Data... 
London - cool, I'm listening to the Resonance fm Mixcloud now
dywen I know, it's with PWM, I believe. I chose the voltage dividers, because I have to figure out PWM with Pure Data...
No you wouldn't need PWM: that is just one of the available options. Figure 3-3 shows how to do it with a DAC: simply connect it through a 10k resistor.
giuliomoro
I know DAC as Digital to analog conversion in sound (sample rate 44100 hz, bit depth etc)
I have to confess that DAC in this option I did not understand.
--> SO if I connect to Bela with the Bela digital out and the 10K, what does Bela, hence Pure Data send?
Bela's analog outs are a DAC, whose output is scaled between 0 and 5V (corresponding to the Pd range 0 to 1). So I was thinking that if for whatever reason you need the voltage on the pin to be adjustable programmatically (e.g.: different sensitivity over time, maybe in response to patch parameters/state), you could do so by connecting analog out 0 to MTSA and then send to it within Pd:
[sig~ 0.5]
|
[dac~ 3] <<< corresponds to analogOut 00.5 gives it 2.5V (scaling the 0..1 range to 0V..5V).
Not sure if this is any useful for your case, I just thought it was a neat feature.
giuliomoro hey, yes, it is a totally neat feature, this would give the switch chip potential theremin like features, gradual because it has to reset, but perhaps workable with bit detoriation for example.
Super!
Works like a charm. Soooooo nice to end my work morning (I have to take care of a lovely almost 4 year old, other parent starts working after lunch)
