Musical Coil Driver

We are now taking pre-orders for version 2.0 of the driver board, this revision features and all new oscillator based on the MCP6542 dual comparator chip that is capable of a whole bunch more interesting high-voltage projects.

Details Here

Bored with your old synth? Think most MIDI output devices are just so last millenium? What you need is the Artifactory's very own 30,000 volt musical ignition coil driver!

The Coil Driver Kit is licensed under the TAPR Noncommercial Hardware License.
Design files will be published before we sell any. We are holding off putting the design files up online until after we are satisfied that the design is both safe and operating within acceptable parameters.

SKoT decided that the hackerspace needed something that went ZAP, in aid of this he acquired a Silicon Chip magazine jacobs ladder kit and commanded that his minions Brett & Daniel immediately set to work. Less than an hour after its completion, it was decided that it was lacking something, and that something was the capacity to play Tchaikovsky's 1812 overture alongside our internet-controlled smoke ring cannon (set to play the part of the cannons in the crescendo!) which had been completed a week earlier. Some burns, minor nerve damage and lacerations later, a working solution was discovered by bypassing the kit's ubiquitous 555 timer and inserting an opto-coupler allowing the connection of a Freetronics TwentyTen. Shortly thereafter a hardcoded version of the Star Wars Imperial March could be heard throughout the Artifactory and by anyone trying to listen to an AM band radio. Could this be it? Our goal achieved, NO, the notes were sour, crackling feebly in the slightest draught, the age old catch cry was heard, MORE POWER! And so was born the project you see chronicled here, the quest for crisp notes and robust arcs, the Musical Coil Driver.

SKoT, being the preeminent master of all things MIDI that he is, has allowed our high voltage villainry to work seamlessly(ish) with a MIDI keyboard.

Extensive destructive testing has resulted in 3 failures of the IGBT, each with a confoundingly different failure mode. Thermal failure in v0.1 due to switching loss resulted in SCR like behaviour but not a full failure, rectified by improved driver design (v0.2).

ESD damage in v0.2a due to handling resulted in partial destruction of IGBT gate insulator oxide layer resulting in total failure under extended load, full closed circuit behavior, rectified by addition of gate protection zener.

Unanticipated arcing from HV to LV side of coil resulted in complete destruction of IGBT gate insulator oxide layer, open circuit behaviour at collector with dead short from gate to emitter, NPN transistor got very hot, rectified by addition of gate protection zener.

• Prototype Production
• Prototype Testing
• Send for pilot PCB Manufacture
• Local PCB Testing
• Kits out for testing with beta testers
• Review & Redesign (If Needed)
• Production!

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We have gotten our initial shipment of 50 PCB's and as expected, we have already found a few minor issues and elements we would like to change. The 10w 1Ω resistor is getting warmer than we would like. 20w power dissipation seems more appropriate. Additionally we have some cosmetic changes to the board that will be included in version 1.1.

If you are interested in acquiring a kit or being a tester, contact Daniel at atrophy at artifactory dot org dot au.