Hey there!
I'm currently working with a 7-Segment flip display comprised of seven solenoids.
I'm using some darlington arrays to drive the wires to flip the solenoids.
The mechanism is interesting because each unit has one black wire (common), seven orange wires (on) and seven red wires (off). So each solenoid has a wire that when grounded will flip it one way, and when the other is grounded it will flip the other way.
I'm trying to get two of these units to share the same bus, and simply add an 'enable' on the common wire to get only one solenoid to process a command if I so choose.
The problem is that I can't just set common to ground, because instead of deactivating the unit, it simply reverses the polarity of the wires, so the display will still respond to the signals meant for the other!
I have attached a graphic explaining the problem.
Is there a way to get this done without a relay? I was thinking either an optocoupler or some kind of transistor high-side switching, or a tri-state buffer, but I'm unsure.
Any pointers would be awesome.
Thanks so much!
