Hello Shep
Some words about the power supply. I would change the inductor to a higher value, about 100uH. And RSENSE to 0.05R, which could deliver about 50mA. C4 is fine, but 4,7u would be enough. Here is a very fine and detailed power supply using the MAX1771 http://desmith.net/NMdS/Electronics/NixiePSU.html For direct driving, you could use the HV5122 or a similar device. But you would need a 5V to 12V level shifter. If you need more info, i can provide. Am Mittwoch, 30. März 2016 23:41:58 UTC+2 schrieb Asstroman: > > Hello Jonathan, > > I may eventually end up using a fixed voltage regulator but the reason I > have an LM317 in this schematic is that I already have these and necessary > resistors so it was mainly just to keep cost down. And that's an excellent > point about multiplexing that I hadn't really though of so I thank you for > that. After this and the previous comments I think I may just use direct > drive. I'm not sure why but I was originally thinking that multiplexing > would be more feasible because I wasn't sure if I could get enough power > out the power supply. But after I took another look at it I think the power > supply will have no problem driving the necessary ~38mA. I'm still weighing > the pros and cons as I figure them out. > > Shep > > On Tuesday, March 29, 2016 at 1:04:19 PM UTC-6, Asstroman wrote: >> >> Hello, this is my first post here in the NeoNixie group so I hope this is >> an acceptable thread topic. I'm excited to find other people interested in >> this sort of thing to get some feedback if anyone has it to offer. >> Attached is a preliminary schematic that I designed for my first go at a >> Nixie clock. (When I say I designed I mean pieced together from the >> internet and filled in some gaps). I'd greatly appreciate any feedback >> anyone has on it concerning better methods or any major problems that would >> prevent if from working. Eventually I'd like to add in more features like >> acquiring the time via WiFi or GPS, temperature sensing and better dimming >> control and such, but for now I'm keeping it relatively bare bones (I >> think). I'm using an Atmega328p as the uC which will be communicating via >> I2C with a MAX1771ESA+ RTC chip. Even though I know multiplexing shortens >> the lifespan of the tubes I've decided to go with using MUXing because I'm >> not so knowledgeable on SMPSupplies (yet) and don't quite know how to get >> the necessary current out of one to use Direct Drive. My scheme is to use a >> 3:8 encoder on the anode side to select which anode is on. And on the >> cathode side I'm using a bin-decimal converter to select which digit is >> displayed. Each digit of a tube is attached to the same digit on the other >> tubes so that when the bin-decimal converter turns on the base, say for the >> "1"s transistor, all the "1"s for each tube will turn on on the cathode >> side, but only the correct anode will be on, thus displaying only the >> correct number on the intended tube. I haven't seen another design that >> does exactly this in the same way so I am not 100% confident it will work. >> It seems pretty straight forward, but then again, as with all electronics >> projects it probably isn't. I will include in my code some measures to >> avoid cathode poisoning, however, I just learned of another issue which is >> blue spots appearing somewhere on the anode mesh... I think. I still need >> to do some research about this and how to avoid it but if anyone has any >> knowledge about this they'd like to share I would appreciate it as I'd like >> to avoid this from happening in my design. Thanks for your time and I look >> forward to any and all responses. >> >> >> Shep >> >> >> >> <https://lh3.googleusercontent.com/-RRq4J135lbY/VvrQxlYW6XI/AAAAAAAAAIc/2oLMtnUf_D8VJ-XBmZ1EXu7h3Dj5EsVsQ/s1600/PG1.png> >> >> >> >> >> <https://lh3.googleusercontent.com/-X4PchxD2EL0/VvrQiT0novI/AAAAAAAAAIU/cnEds-f5Ogw4bWnU0JzZSScAFpwxayLbw/s1600/PG2.png> >> >> >> > -- 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/e8fb7b31-abb1-4b0b-b9dd-d0c28972183b%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
