A similar 'nasty' can happen to experimenters - if multiple voltages are required on a board, don't 'common up' at the bench supplies with only one common taken to the board. Lifting that common causes the 'total' voltage to distribute according to the various resistances - eg your 3V ICs could get most of the 12V IC's voltage. [If you are new to electronics, try some calculations. OR just take my word for it.]
Which is also why I don't like multi-phase mains distribution in houses. Had to provide 'consultation' to a local hotel. The electrician put the damage down to a 'mains spike'. He had lifted the Neutral at the main switchboard as part of his RCD and compliance testing [he had added a new run]. This meant that the large airconditioner [high current] and the clocks/radios/tv/microwaves were in series across 415V line-to-line. John K Australia ----- Original Message ----- From: gregebert To: neonixie-l@googlegroups.com Sent: Thursday, April 23, 2015 5:43 AM Subject: [neonixie-l] Re: 7 digit nixie preliminary design Make sure you pay close attention to the datasheet regarding power-sequencing. Many CMOS devices with multiple power supplies require them to be brought up (and down) in a specific order, otherwise internal damage will result. You wouldn't believe all the effort we go to at my day-job not only to ensure correct power-sequencing, but also to identify all of the possible failure modes if sequencing is wrong. -- 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 neonixie-l+unsubscr...@googlegroups.com. To post to this group, send email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/64c1aabd-6700-4e5d-9261-758577440b76%40googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- 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 neonixie-l+unsubscr...@googlegroups.com. To post to this group, send an email to neonixie-l@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/73E5E5386FF9405087DDF531D46C729F%40compunet4f9da9. For more options, visit https://groups.google.com/d/optout.
