The 3.3V pin can handle up to 50mA of current, and supposedly more if you use the 5V input power pin rather than the 8V to 20V. I will be using 10mA LEDs I plan on using this setup, 12V car wire ---> buck converter ------> Arduino Nano 5V input pin. Like you said auto voltage has a lot of spikes and inconsistency, at least cars now have alternators instead of DC generators that would make the lights brighter when you gave the car gas lol. Now the SMD HV supply for the Nixies will be ran from the car wire, but I figure the capacitors can probably handle the voltage spikes.
On Tuesday, September 4, 2018 at 4:15:41 PM UTC-4, gregebert wrote: > > Schematic looks like it has some crossovers, etc. The path for the neon > bulb is: 160 VDC --> Neon bulb ---> Transistor 'C' ---> Transistor 'E' > ---> Emitter resistor ---> GND. Then connect the transistor base to your > Arduino device. > > If you are driving the LEDs directly from the Arduino, be careful with the > current. I dont know how much current your LEDs require vs the output > current of the pin. > For example, if you have 3 LEDs that run at 10mA each, that's a 30mA load > for the Arduino, which is pretty high. > > As an alternative, you could connect all 3 LEDs in series, drive from > +12V, and use a current-limiter transistor similar to what you did for the > neon bulbs. Just recalculate Re from the formula I posted earlier, and use > 10mA and 3,3V. I get something like 260 ohms. > > Lastly, since you are running on a 12V automotive supply, be aware that's > a very nasty environment with all sorts of voltage spikes (alternator > load-dump), dips (engine cranking), and even reverse-polarity (doofus > giving your car a jump start has the cables backwards). It's especially bad > for older vehicles that have mechanical voltage regulators. Even the > method how you wire it will make a difference, depending upon what kinds of > high-current devices share the wiring (fans, A/C compressor, starter, > alternator, electric windows). > -- 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/16e81150-f04b-46d8-a655-3d189e9c9d93%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
