I found some of these power supplies now that put out 0-500VDC 0-2A with 4 sets of outputs. This seems perfect for a four or probably even 6 digit clock if the tubes are driven PWM. The power supplies even have 1V resolution. These power supplies have a fan in them so I'm interested to see how loud they are. I don't really want some loud power supply fan but if you think about it 500V @ 2A o.O that's some 1000 watts we're talking about. So say the power is good now. I'm interested now in the switching of the HV. I'm curious if PCA9685 could be used to PWM using some HV NPN transistors? What we need is a PCB design that can route all these control lines for all these tubes. This is a LOT more than a usual 4 digit clock with 0-9 cathodes to control. One thing that seems nice about the PCA9685 is that the phase of the PWM can be controlled so we could make it so all the tubes don't turn on and off at the exact same time. Has anyone played around with this kind of a configuration before? It would also be nice if the transistors could come in smaller package because geesh we need a F' load of these things on the PCB. The PCA9685 is 16 channel. So 6 would be needed because 23 x 4 = 92 tubes and 92 / 16 = 5.75. I'm kinda thinking out loud here so if I'm totally off on this idea someone please let me know? It seems like I2C control of the tubes duty cycle and phase would be pretty sweet for dimming right?
Bill On Friday, October 16, 2020 at 3:57:34 AM UTC-7 Bill Notfaded wrote: > This is exactly correct Paul and I have both shown the 500V models we have > here. I bought a second 500V one. I like the fact that some have four > outputs too. These are used for genetic research. > > Bill > > On Thu, Oct 15, 2020, 1:20 AM Paolo Cravero <[email protected]> wrote: > >> Hi. >> >> The PS Paul and I have goes to 500V but I've found some that goto 300 >>>> which seems perfect for this with 4 sets of outputs! >>>> >>>> >>>> >>> >> Maybe it is not what Bill meant, but electrophoresis power supplies come >> in ranges up to 300Vdc (minimum) and few dangerously hundred mA. Add a >> current limiting circuit for human safety as suggested by gergebert and >> you're set. Easy to find in US and UK over eBay. With some patience can be >> had with less than 100 USD/EUR/GBP. >> >> Paolo >> >> -- >> You received this message because you are subscribed to a topic in the >> Google Groups "neonixie-l" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/neonixie-l/bVoCKhPv7Dg/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> To view this discussion on the web, visit >> https://groups.google.com/d/msgid/neonixie-l/CABj2Vaaso61iFnB9fD80BUCD1TepGQzNeuXnD8PUG3oiuX9Kkg%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/neonixie-l/CABj2Vaaso61iFnB9fD80BUCD1TepGQzNeuXnD8PUG3oiuX9Kkg%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- 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 view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/0f7f3201-e0a5-48ec-9aaf-370876f874fbn%40googlegroups.com.
