32 Channel Micro Valve Driver

We designed and built this micro-solenoid valve driver system for NeoVac to control gas flow patterns in vacuum coating cathodes, in real time at 40 updates per second.

Each board receives valve flow commands for sixteen valves as a string of bytes from a parallel port. It then provides a pulse width modulated output for each of the sixteen valves.

The reason for this is to unload the main processor, which would otherwise spend most of it's time servicing the valves. By doing this with these boards, we can keep PWM cycles down to 25 mS with 20 uS resolution for all 32 valves.

The processor is a PIC 18C442.