PWM to Analog Voltage Converter

I ran into a signaling issue while developing a print area cooling system for the Bloft Mk2 3D printer based on compressed air. The air pressure was regulated by a proportional valve. The problem was that the printer's mainboard provided only a PWM signal for controlling the RPM of a cooling fan. The valve on the other hand needed an analog control signal 0-5V proportional to the output pressure. So, I had to design a signal converter from a PWM signal to an analog voltage.

2023
R&D, electronic, signal conversion, pcb, milling, soldering
I found an off-the-shelf PWM-to-0-5V converter module, but the signal coming from the printer mainboard had to be inverted and isolated from the module. Not doing so caused too much interference. Luckily I happened to have some isolators and logic gates alongside with the needed passive components. Once the circuit's function was confirmed on a breadboard, I went on and designed a two-sided PCB on KiCad which then was processed on Flatcam and finally milled on our CNC.
For such quick prototypes and small volumes, it is hardly worth the expenses to order PCB's from the factory. It is very quick to make PCB iterations without the shipment delay.
Top side with power circuitry etc.
Top side with power circuitry etc.
Bottom side with PWM to Analog converter
Bottom side with PWM to Analog converter
↑Back to Top