@greg, I have taken a look at this: http://tayloredge.com/storefront/1386_B7971SmartSocket/1386.pdf . When using 175V as supply voltage and assuming 140V voltage drop on the tube, the currents should be:
S15, S4, S1 = 1.59mA S14, S10 = 1.06mA S13, S11, S9, S7 = 1.46mA S12, S8, S6, S5, S3, S2 = 1.30mA When you add them all together, you get 20.53mA which is just right under the specs of the datasheet so I adjusted the currents according to it. I know this will result in less brightness than the maximum possible when all segments are not lit up because plenty of margin will be left then, but I see no other way, other than implementing the anode current limiter as well as you have described in earlier posts. Dana srijeda, 10. svibnja 2017. u 20:26:24 UTC+2, korisnik gregebert napisao je: > > Luka - What segment currents are you using for the 7971 ? > > If you turn all segments on at the rated datasheet current, there are > several characters, such as 8 and Q, that will cause the total current to > significantly exceed the max rating of 22mA. I analyzed current-draw for > most characters, and even the average (~26mA) exceeds spec. > > I scaled-back the current in my design so I never exceed the max 22mA. > > 7971's are really expensive & rare, so I'm not taking any chances. > -- 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/e39361f0-3003-43c9-8612-78e17df62b11%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
