Low Pass Filter for PWM to DC

Example Low Pass using only one resistor and one capacitor
Example Low Pass using only one resistor and one capacitor

I’ve been working on a project where I needed a consistent DAC signal to be sent from a control device to a sensor. The sensor wanted a voltage input which was steady, but arduino boards don’t have true DAC output, rather they use PWM to approximate a voltage over a given time. For many devices (like a simple LED) this is fine, but for higher speed systems, more precision is required. A simple solution is to employ a low pass filter, similar to that described here.

The site mentioned above has an excellent link for calculating your R and C values, based on the input signal your dealing with, which can be found here.

-Austin