Similar here, except I use the HV5530 which is rated for 300V. I strongly discourage using zener diodes, or the nixie-tube itself, to drop-down the voltage to CMOS parts, because even the tiniest amount of leakage thru the diode/nixie will cause the voltage drop to be less than expected, and overstress the CMOS device. You could use an appropriately-sized bleeder resistor to ground, but it's still not rock-solid. Another approach is to use a zener as a clamp at each output but that is wasteful because it requires 1 zener per pin.
On the other hand, if you are using bipolar parts, such as NPN transistors or 7400-series TTL parts, exceeding the voltage is OK as long as the current is limited to a few uA or less. Bipolar devices do not have oxide-insulated structures like CMOS, so they are not inherently destroyed by over-voltage. On Monday, March 3, 2025 at 11:39:00 AM UTC-8 newxito wrote: > I use the HV5622, which goes up to 220 V, I think there is also a PLCC > version. The disadvantages are the price and that it should be operated > with 12V according to spec. However, I never had any problems using the > chip with 5V. > JBro63 schrieb am Montag, 3. März 2025 um 19:02:56 UTC+1: > >> Hi all, >> >> Group noob here, about to start build on a few different types of display >> using Nixie tubes and ESP32. >> >> Planning to use K155ID1 initially (as I have a bunch) with some IN-12 and >> IN14 tubes but want to also try HV driver such as the 5812 or 5530 so would >> welcome any comment on which is the best one to go for or an alternative. I >> don't intend to multiplex. Any driver would need to be DIP or PLCC. >> >> Have spent many hours looking at the schematics and designs of others, >> I'm grasping the basics but one frustration and evident gap in my knowledge >> is how to pick / calculate the correct component and its size or rating for >> anything other than the most basic circuit. >> >> For example, with a 180v supply, calculating the anode resistor for a >> tube based on the datasheet is straight forward enough as the maintaining >> voltage and current are known. >> >> When looking at something like the HV5812, many seem to use a 60 or 70V >> zener diode with a resistor to keep below the max for the chip but how do >> you determine the current needed for the driver, diode and load to be able >> to calculate the current limiting resistor? The diode datasheet is simple >> enough but I'm lost with the sheet for the HV5812. >> >> Thanks. >> >> -- 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, visit https://groups.google.com/d/msgid/neonixie-l/fb14cbfe-fb29-4281-b82c-73e257710d60n%40googlegroups.com.
