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elec:avr:t84:insoled

# InsoLED

## Overview

In a few words, it's a LED-based PCB exposure box. Most designs of PCB exposure boxes are based around UV-tubes, or a lot of 5mm UV leds. I chose to try with 1W UV-LEDs. The design aims to be:

* Portable

  • Not fragile, like UV-tubes are.
  • Small, since I rarely need to expose an A4-sized PCB.
  • Big enough for standard sizes of PCB, I chose to go with 100x160mm which is already more than what I'm used to.

* Easy to use

  • Autonomous: Put your PCB in, start, come back when it's done
  • Adjustable, since different PCB, traces sizes, … require different exposure parameters.

* Easy to make

  • Don't reinvent the wheel, at least at first… I chose to go with a cheap LED driver from eBay instead of building one.
  • Use cheap, easy to source, generic parts…
  • Use common, on-hand tools and materials

* Expandable: Need a bigger one? Just add some LEDs and make a bigger case. * Safe: Yeah, this one too… Enclose the UV stuff.

## Pictures

dsc_0178.jpg dsc_0180.jpg dsc_0181.jpg dsc_0183.jpg

* The first one is the first prototype, on a breadboard, with a Teensy2.0 instead of an Attiny44 * The next two are the actual prototype (there was a mistake on the PCB, involving a quick fix to get the backlight) * The last one is the Power Interface to drive the LEDs, it's a phototransistor (4n35), followed by a N-Channel Power MOSFET. And yes, this is … messy, but it works as expected, so I might integrate it in the next revision of the PCB

<note tip>The PCB of the Timer was made on the prototype of the exposure box ^^</note>

## PCB

### Version 1

I haven't built this one…

### Version 2

There's a small mistake the LCD Backlight must go to GND and not to Vcc…

### Version 3

Version 3 has moved to SMD parts (opto-transistor, Attiny44 and resistors). The MOSFET is now integrated on the PCB…

## Case

The case is made of PVC (and PMMA for the bottom I think) cut on a small CNC. I first made a design on Catia V5, to see where to place the LEDs and stuff, and then redesigned the parts on Galaad, which was a good training exercise.

The top is still to be defined, but I think it'll be in two parts, one to hold/hide the electronics, the other, on hinges, to hold the LEDs and allow access to the PCB that's being exposed.

## SVN Repository

Right now, that's the only resource available. The whole project is under GPLv3, so feel free to improve it.

  svn co http://svn.redox.ws/svn/InsoLED

. ## Bugs, improvements

I've set up a Tracker for bug reports, suggestions, … Here

/home/share/www/redox.ws/wiki/data/pages/elec/avr/t84/insoled.txt · Last modified: 2023/11/24 21:55 by 127.0.0.1