It is my intention to use a HTCC-AB01 board with two sensors, a wind speed and a wind direction sensor. The output voltage of the wind speed sensor is 2-4 volt and the output voltage of the wind direction sensor is 0-5 volt.
Can someone tell me which pins I can use to connect those two sensors? And what is the maximum voltage on those pins?
hi,
I’m afraid this won’t work. AB01’s GPIOs can only withstand voltages less than 3.7V for a long time.
Hi Jason, thanks for your help.
I think this voltages restriction should not be a problem as long as I use a voltage divider to reduce the voltage or am I wrong?
And which pin(s) do you advice for analogRead() from the sensor?
Regards, Hans.
you are right.
you can use this pin:
Great and thanks for helping. Appreciated!
Hi Jason, sorry to be back but things went wrong.
The 0-5 volt sensor output is reduced from 0-3.6 volt using the voltage divider to be compatible with the Cubecell board (see image).
The ground from the divider will be connected to the Cubecell ground (upper left pin) and the positive output from the divider to the ADC pin (bottom right) of the board.
When the power from the divider is at 3.6 volt it is reduced to about 2.8 volt as soon as I connect it to the ADC pin of the board.
To me it looks this is not correct, any idea what’s wrong?
Hi,
You can try to remove this 0R resistor.
Hi Jason,
I did not dare to desolder the SMD resistor but modified the voltage divider so the output is max 2.4 volt to the ADC pin.
Although the ADC pin withstand voltage is 3.7V, things went wrong if it exceeds 2.8 volt. By limiting to 2.4 volt my wind direction data is available from 0-360 degrees.
Regards, Hans.
hi,
please refer the picture:
