Small update:
After some further research, I've decided that those current limiting diodes are a bit too expensive for the clock (6 x 15 = 90 diodes). I've implemented a current source using a depletion type MOSFET along with a resistor like in the attachment, I'll test it out and see how it works. Since these types of MOSFET have some margin in the Vgs between batches (apparently the Vgs is written on each reel), I'll adjust the resistor size after purchasing a lot of them first. Dana ponedjeljak, 27. veljače 2017. u 18:32:10 UTC+1, korisnik gregebert napisao je: > > I see no reason why it wouldn't work; the voltage-drop across the diode > will vary as needed to limit the current. This is the typical behavior of a > current source; even a resistor behaves somewhat in this manner. The > datasheet states the device can handle 600mW, so if you are running at 6mA > or below, you wont have a thermal problem as long as the POV spec (100V) is > followed. > > Regarding constant voltage across the nixie tube, it's a consequence of > how it operates. You want to limit the current to the datasheet spec; this > can be done with a resistor or a current-source. Whichever approach you > take is a matter of choice; I prefer current-limiting because it gives > tighter control and can be more energy-efficient. > > Glow tubes have a nonlinear I-V curve that becomes steep after ionization, > which means that a small change in voltage will cause a large change in > current. Even LED's behave this way. That's why you can't just drive them > from a constant voltage, like an incandescent bulb; there needs to be > something to limit the current. > > If you still feel nervous, test it out with a spare or expendable nixie > tube (IN-1's are cheap...). Just make sure the diode is installed > correctly; if it's backwards...bye bye nixie.....Unfortunately the > datasheet doesn't show the test-circuit, which is unusual. > -- 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/9083295b-be82-45ed-a9a4-62e353110c3c%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
