On Tuesday, December 3, 2013 12:43:04 AM UTC-5, jrehwin wrote: > > > I hope someone out there has some thoughts on this and is willing to > help out this noob. > > > > The senerio is this: > > > > I am attempting to use an Arduino in conjunction with a TLC5940 to drive > an array of IN-9's (And not kill myself or blow anything up) the problem > being if i understand it right (which I probably don't) is that instead of > a positive PWM out the arduino the TLC5940 works by sinking the current on > the cathode side. I don't think i can use this with my standard mpsa42 (and > I'm not going to attempt anything until i get some advice) I do have some > mpsa92's available. > > That's a somehat peculiar choice for driving an IN-9, but if that's the > way you're going, you'll want a common-base setup for your transistor, to > provide voltage gain but not current gain (the current through the IN-9 > will still be controlled by the TLC5940). You could use your MPSA42 for > this (note that I'm just scribbling here, this lashup might not work): > > http://www.vitriol.com/images/tech/nixies/TLC5940.gif > > Have you read Jan's writeup on driving IN-9s? > > http://www.die-wuestens.de/iz/IN9-2.pdf > > You might also want to look at some other designs used to drive IN-9s, > such as Brian Stuckey's Nixietherm: > > > http://www.tubeclockdb.com/forum/Builders-Forum/1280-Nixietherm-IN-9-bargraph-based-thermomer.html > > > - John >
Thanks for the quick reply John, the main reason for he 5940 in this case is that an arduino does not have enough pwm outs to drive the 14x in-9 array for my "spectrum analyzer" probably actually an audio visualizer. Yes I have read that write up on driving in-9's and have done a few projects with that already. After much research I found something very similar to the lash up you posted. I just have to figure out weather the 5940 will sink that much current. If you have any other ideas for driving 14 of them I am all ears I've been thinking on it for months I could use a fresh mind. I am sure there is a better way to go about all of this. That's what I get for being a noob. Thanks again John Chase -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/d2cb8913-648d-46c7-9878-95050569a952%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
