Friday, October 22, 2010

Testub es electronics - safety conscious now

I spent all of this week developing a permanent hardware solution that I would be able to mount an arduino to without fear of frying yet another chip (they aren't that cheap). I build on top of a protoboard simply for the convenience of having a permanent solution that would be robust but still not too hard to re-route wire if I screwed up.

I really did not want to screw up another chip so I electrically isolated the arduino from the 12V components through the use of DIP package opto-couplers. Opto-couplers(or isolators) are really awesome devices that use a led and a phototransistor as a switch. They can accept over 700V in the wrong direction before they might short out which is awesome for a protection device. My circuit uses 5 of these - four for the steppers and one for the solenoid. I found a circuit diagram online from from which I based my circuit diagram for the solenoid on. This one was important to get right as solenoids have high transient reverse voltages when they switch, which can be very damaging for some components. The solenoid circuit uses a high power mosfet to handle these large voltages.

Lastly I put a diode on the power supply to make sure I don't screw up when putting plugging it in.

I'm actually very proud of the circuit because it is by far the most complex I have every done, and I designed the majority of the logic from scratch.

Tags: electronics

Comments

Add a comment

Name:

Website:

Comment:

Twitter username: (if you want to be informed of replies to your comment via twitter)

If entered, the twitter username field is used to subscribe to replies to your comment. When someone replies, a tweet will be posted to @yourusername.

All comments are moderated before being posted, so be nice.

All fields are optional, your twitter username will not be public if you choose to put it in

Related Posts:

Post Posted Relatedness
Changing focus 11 months later ×
Smart Systems - New Idea 11 months later ×
Arduino Grapher progress 12 months later ×
Semi successful copper deposit on curved plastic 10 months later ×
First attempt at depositing copper 10 months later ×
Testub es hardware and software 1 week earlier ×
Arduino Grapher beta release 1 year later ×
Curved printed circuit boards 10 months later ×
High speed photography 10 months earlier ×

Tags