nRF51 Capacitive Sensing Output Value

RE: nRF51 Capacitive Sensing Output Value

Peace Makes Plenty — Mon, 21 Jan 2019 15:12:19 GMT

Thanks for the clarification and reaching out to the developers.

RE: nRF51 Capacitive Sensing Output Value

ovrebekk — Mon, 21 Jan 2019 08:22:14 GMT

Hi again

The developers didn't have any more info about this unfortunately. The voltage corresponds to the capacitance, but exactly how it scales with the capacitance is unknown.

Best regards
Torbjørn

RE: nRF51 Capacitive Sensing Output Value

awneil — Thu, 17 Jan 2019 14:10:24 GMT

[quote userid="2116" url="~/f/nordic-q-a/42564/nrf51-capacitive-sensing-output-value/166259"]normally that is not a requirement since you only want to know if the sensor is touched or not[/quote]

Agree.

RE: nRF51 Capacitive Sensing Output Value

ovrebekk — Thu, 17 Jan 2019 13:46:54 GMT

According to the documentation the output for the nRF51 version of the library is a voltage in millivolts, where "voltage corresponds to capacitance of the pad attached to analog channel and gets higher once it is touched"

The voltages reported will change based on the sensor you are using, and how it is mounted, so you need to do some experimentation to figure out the right threshold values for your sensor.

I can check with the developers if there is any way to calculate the actual capacitance based on this value, but normally that is not a requirement since you only want to know if the sensor is touched or not.

Best regards
Torbjørn