Ooops, sorry Gregebert, I'm not experienced with google groups and I didn't know the difference between reply to group vs. reply to author.
I'm going to repeat my question so it's group visible: Basically I was wondering for multiplexed vs direct drive, if given the same voltage and current limiting resistor, would the max brightness of the multiplexed tubes be basically like the direct drive tubes operating at 1/6 pwm ratio? It might not be 1/6 brightness due to non-linearity, and maybe additional effects based on frequency of the pwm or multiplexing. But in that case, there shouldn't be any additional wear on the tubes right? The wear only comes from if you want to increase the multiplexed tube's brightness even more, to match a direct drive with a higher pwm ratio? I was wondering because I thought about going multiplexed to save on board space and soldering time. On Tuesday, 13 July 2021 at 05:26:50 UTC-4 andybiker wrote: > It's also worth mentioning that with a multiplexed design it's easy to dim > the tubes for a dark room and obviously extend the life. > I have a bedroom arduino-based clock that has 4x NL5780 multiplexed. > The brightness auto-dims so that it's nice at night (and at a level that > would be invisible during the day) and then is bright during the day. > > On Tuesday, July 13, 2021 at 6:28:29 AM UTC+1 owen.cra...@gmail.com wrote: > >> Makes perfect sense. Thank you for the explanation. Think I'll be going >> down the direct drive route for my designs. >> >> On Tuesday, 13 July 2021 at 14:43:30 UTC+10 gregebert wrote: >> >>> If you use 1 decoder for 6 tubes, the duty-cycle is 1/6 and it will >>> require more current to get the same brightness as a tube with a higher >>> duty-cycle. So, if you use 2 decoders, the duty-cycle is 1/3 and the peak >>> current will be less vs 1/6 duty cycle. >>> >>> Personally, I never multiplex tubes because it requires more current per >>> tube, and the wearout mechanism for tubes (sputtering), increases >>> exponentially with current. In my opinion, IC's are cheap and readily >>> available whereas nixies are much more expensive and getting harder to >>> find, so it makes the most sense to drive the tube as gently as possible, >>> ie direct-drive, to prolong their life. >>> >>> On Monday, July 12, 2021 at 8:00:07 PM UTC-7 owen.cra...@gmail.com >>> wrote: >>> >>>> A little but of a noob question, though looking around at different >>>> multiplex clock designs, I see that some setups opt for 2 x K155ID1and >>>> others only have 1. >>>> >>>> A classic example with 2 x drivers would be: >>>> http://www.arduinix.com/Main/Gallery.htm >>>> >>>> Then I find others with just 1 x drivers: >>>> https://www.instructables.com/simple-user-adjustable-DIY-Nixie-Clock/ >>>> And: https://www.nixieclock.biz/StoreClassicRev5.html >>>> >>>> Why is this the case? I have also seen similar sketch codes to drive >>>> both single and double drivers, so I am wondering what the decision >>>> process >>>> around this is and if it's even necessary to have 2 drivers to begin with? >>>> >>> -- 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 neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/cd8c7e6c-41ea-4820-9919-cc40286db90an%40googlegroups.com.
