I am only driving one tube otherwise I would use such a chip or the HV5812P-G serial-in which does not seem to need a negative supply. You probably have a good reason for your choice. My last schematic has errors which I have corrected below. I did not know the pin numbers for the IV12. These are correct and the display works. Another error on the first schematic was, after all my talk of polarities, grounding PH instead of pulling it high. Here is the corrected schematic that works. The filament draws 100mA and I can save over half of that if I need to by using a switching regulator as suggested. This is simpler. [image: VFD IV12 Schematic.jpg]
On Sat, Jan 30, 2021 at 2:37 PM gregebert <[email protected]> wrote: > I'm contemplating the HV57009 for my upcoming VFD clocks; it requires a > negative supply so that presents some challenges but a single device can > drive 64 segments at 2mA each. > > On Saturday, January 30, 2021 at 9:48:06 AM UTC-8 [email protected] wrote: > >> Thanks Davis; I think I have a solution but will look at your suggestion. >> The CD4543 seemed to only drive a milliamp or less but I found I had six >> MC14543B which will drive 10mA source or sink. >> This should do it. I will need to find out what anode voltage I need and >> choose a power supply, probably running off 5v. >> Pin 6 (PHase) sets either active high or active low outputs. It is driven >> by a square wave for LCD displays. >> I left out that my intention is to add a selection of LEDs that will be >> in the opening at the front. >> I'm off to test the circuit. Peter. >> [image: VFD IV12 Schematic.jpg] >> [image: 20201227_104715.jpg] >> >> On Sat, Jan 30, 2021 at 11:19 AM David Pye <[email protected]> wrote: >> >>> Hi Peter, >>> >>> For my vfd clock project (https://github.com/davidmpye/VFD), I used the >>> following high side driver ICs (I used one per tube but of course I >>> could've multiplexed) >>> >>> They are either known as UDN2981 and there's also a Toshiba version >>> (TDSsomething). They aren't BCD though - just one pin per segment, so that >>> might not be any good for your application depending on how many IO pins >>> you have spare .. >>> >>> David >>> >>> On Sat, 30 Jan 2021, 00:57 peter bunge, <[email protected]> wrote: >>> >>>> I need to drive a single IV12 vacuum fluorescent display from a BCD to >>>> 7 segment chip. >>>> I could use level shifters like the CD40109B or CD4504B but they don't >>>> have 7 devices in one chip (4 and 6) and only drive 18 volts which might >>>> work. >>>> I could use a ULN2803 transistor array with 7 pullup resistors on the >>>> outputs. The problem is the BCD to 7 decoders (e.g. CD4511) are usually >>>> active high, which I need, but the ULN2803 is an inverter which I don't >>>> need. A CD4543B might work as the BCD to 7 and can be selected for inverted >>>> outputs but it is designed for LCDs not driving transistors. >>>> The 74LS47 has the right polarity to drive the transistor array but it >>>> has open collector outputs so 7 more resistors are required. >>>> Any suggestions that don't get even more complicated (shift registers, >>>> octal inverters, arduinos, etc) >>>> I'm looking for a convenient driver chip. >>>> >>>> -- >>>> 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/272c6223-da83-44e2-b180-dfb3bc46b40en%40googlegroups.com >>>> <https://groups.google.com/d/msgid/neonixie-l/272c6223-da83-44e2-b180-dfb3bc46b40en%40googlegroups.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/CAOQ6x0G4aQbJt3BHbcZCi7qFZ971SyYfDCdw-UZfOPiFB4GXZQ%40mail.gmail.com >>> <https://groups.google.com/d/msgid/neonixie-l/CAOQ6x0G4aQbJt3BHbcZCi7qFZ971SyYfDCdw-UZfOPiFB4GXZQ%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/47bb1981-ad81-4f16-89f2-7976148775afn%40googlegroups.com > <https://groups.google.com/d/msgid/neonixie-l/47bb1981-ad81-4f16-89f2-7976148775afn%40googlegroups.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/CAFxqQoKJKUYmi6vzn7zTh%2B7pfvpE22erZMkBfKmSVDkNxTVRmQ%40mail.gmail.com.
