PPM Input

PPM Input

If you have a PPM signal that is higher than 3.3Volts you will need a voltage divider to reduce the signal. Otherwise you !Will! damage your BLE Nano 33.

Hook up as shown in the diagram below. To calculate R1 use the following formula.

For 5V PPM signal, R1 = (5*10,000)/3.3 - 10,000 = 5151ohms Round the value UP to the nearest commonly available resistor, which is 5600ohm or 5.6k

For 7V PPM Signal, R1 = 7*10,000/3.3 - 10,000 = 11,212 ohms ==> Rounded Up ==> 12,000ohm or 12 Kohm

It's better to have R value too big, this will result in a lower voltage on the output, which is okay as it will still be detected as a high level.