For direct-drive, you can just let the cathodes float, and they will be completely dark unless your driver has leakage. I've done 5 full designs with direct-drive that floats the cathode, and none has any issues. All told, there are 52 nixie devices in operation with no hint of failure or leakage. 24 of those tubes have been in service 24/7 for the past 8 years.
There are some variations in the design, mainly for cathode and/or anode-current limiting but they all float the 'off' cathodes. Admittedly, I've never done a multiplexed design with nixies, only with LEDs, and unless the nixie tube is specifically designed for multiplex operation I would stay with direct-drive. The reason I follow is that multiplexed digits need a higher pulsed current to maintain visible brightness, and higher current leads to tube wearout. -- 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 post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/e168a850-f3d7-4e88-adc8-1b3bd32b1902%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
