I'm a bit concerned about spacing between pads. The device states it is able to switch voltages as high as 220V. The QFN package has spacing between the pads is nominally 0,25mm. This is violating norms about PCB spacing vs. voltage, the least strict norm I found states that 0,4mm spacing is required between traces with 220V between them - and that's for coated PCB, pads should have even higher spacing. Add to that the fact, that the IC will not be places 100% at the right spot, which will tighten pad-to-pad distance even more.
Of course, this should generally work, just like Chinese 230V/5V adapters, which often run secondary voltage traces very close to primary (and I haven't seen a single one which had the air gap actually cut - only marked). They do violate design rules, but at the same time, they do their job. In nixie world enviroment all of this shouldn't matter - while a tube is connected just via the anode, it doesn't mean that cathodes are at anode potential. Cathodes are ~110V lower than anode potential, they will always represent a voltage drop of at least some value. That means that we can ignore some of the problems, because with a 180V supply, the Supertex piece will see only about 70V, which requires only 0,13mm spacing. Still, the uncoated spacing (pads) should be wider than this value. I also do not know if leftover flux increases or decreases breakdown voltage of pad-to-pad spacing, and in such piece I highly believe that there will be a small space between PCB and IC, in which leftover flux will be gathering, and it will be not removable. W dniu sobota, 28 października 2017 19:33:45 UTC+2 użytkownik SWISSNIXIE - Jonathan F. napisał: > > > Hi folks, > > We all know the PLCC Style HV-Drivers from Microchip, for example HV5530. > All of them require a +12V Data Signal according to datasheet, but yet the > run in some circuits with even 5V data signals.. > > > While browsing microchips website i found HV5523/HV5623. > http://ww1.microchip.com/downloads/en/DeviceDoc/hv5523.pdf > <http://www.google.com/url?q=http%3A%2F%2Fww1.microchip.com%2Fdownloads%2Fen%2FDeviceDoc%2Fhv5523.pdf&sa=D&sntz=1&usg=AFQjCNG0mN-AXhAEOyZ8dfDc072snc2eTA> > > > > Those are fast 16Mhz registers with 5V logic data and can switch up to > 220V@100mA per Channel and come in a very small QFN package. (Attached an > image to PLCC for comparision) > I will definitly order some of them to test :) they would help to make a > very slim and thin clock board :) > > > > Has anyone experimented with them already? Something to know? > > > -- 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 post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/3d9bf2bd-3b52-4c63-845d-d2a6b113f574%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
