Have you looked at what the different chip manufacturers offer? Most of them are involved with this nowadays in one way or the other, for instance Maxim have this to say in one of their application notes: https://www.maximintegrated.com/en/design/technical-documents/app-notes/4/4213.html
*VIN Range*: The voltage transient range on a 12V battery powerline determines the input voltage range of converter ICs. A typical car battery operates in the 9V to 16V range. The nominal voltage of a healthy battery is 12V when the engine is off, and around 14.4V when the engine is on. This range, however, easily extends to ±100V when the transient conditions are involved. For the full specification of these transients, please refer to the ISO7637-1 industry standard. *Figures 1* and *2* are part of this ISO7637 standard and outline the most critical conditions that need to be addressed by a high-voltage converter in an automotive power supply. Besides the ISO7637-1, there are new transient conditions defined for battery-operated or environmentally friendly gas engines. Most of the new specifications are driven by individual OEMs and do not necessarily follow an industry standard. Nonetheless, overvoltage and undervoltage protection are required for all new systems. [image: 1.gif] *Figure 1. A cold crank profile.* [image: 2.gif] *Figure 2. A load dump profile.* /Martin On Friday, 9 October 2020 at 04:47:59 UTC+2 Paul Andrews wrote: > I want to power a nixie device from a car power socket - the things that > used to house cigarette lighters. I figure I need to clean up the power, as > well as source an adapter and probably a cable with a power plug on the > end. I seem to have a few options: > > > 1. Use a 5V USB adapter > 2. Use a multi-voltage adapter like this one > > <https://www.amazon.com/Powseed-Universal-Adapter-Speakers-Electronics/dp/B07BSFSW8N/ref=sr_1_12?crid=14ZWQ57FRTCXZ&dchild=1&keywords=car+power+adapter&qid=1602207108&sprefix=car+power+%2Caps%2C157&sr=8-12> > 3. Build a power sanitizer from a resistor, diode and capacitor as > suggested in this post > <https://forum.arduino.cc/index.php?topic=287394.msg2013378#msg2013378> > on the arduino forums, and feed it to a 5V regulator. > > Is the power provided to a modern car power port that dirty to start with? > Would either of the adapters (1 and 2) likely provide clean power? Option 3 > appeals to the DIYer in me, but would end up being more expensive than the > other two. OTH, I could eventually build it all into one enclosure if I end > up going that far. > > I guess another question is: Would the power provided to an ODB2 port be > clean? > -- 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/5e3290eb-bacd-400d-8ff3-9321c03872dan%40googlegroups.com.
