We're using 3d printers and looking to do part cooling using compressed air rather than a fan (gives more precise and much more cooling capacity). We're using the Duet controller, which gives PWM control of fan outputs. However, the proportional valve we would like to use takes current control http://www.smcpneumatics.com/assets/images/pdf/PVQ.pdf and it looks like we need to provide something between 120-130mA to 170mA to provide the full range of flow control as we will be operating at ~5psi and below. So... if you have any idea how to solve this problem and happy to help a noob out... I would be super appreciative!