There must be some simple answer to your problem. It seems to me as if the 555 might not be doing any switching, or doing it incorrectly. Or as you say the FET is not all it's cracked up to be, or the diode is not fast enough. Check the value and rating of your inductor.
The FET should not get too hot. Usually it will run cool enough for you to hold it.
John S On 18 Nov 2011, at 19:43, Imbanon wrote:
Hi all.Yeah, another thread about this supply.. http://www.ledsales.com.au/ kits/nixie_supply.pdfI know I could and should have made that Maxim power supply, but I didn't. So now I'm stuck fixing this with loads of spare parts I've got... except for the FETs.. Anyways, the supply isn't working. The first one I made worked just fine for 15 minutes, powering 6 IN-14 at 170 volts (multiplexed). Then I set it to 200 volts (to get RMS of 2mA), which worked for 5 minutes, and then smoked and failed. I made another on a quick PCB, which just smoked immediately when I switched it on. The same thing happened to the newest, breadboarded one. The MOSFET seems to overheat instantly and smoke out. Having nothing to lose (except the molten hole in the breadboard), I left it powered, to see the diode smoking next. Aparently, its still in working order (so says the multimeter). Heat sinking FET only makes it last longer in not working state before it smokes. I tried replacing inductors, 555s, diodes, transistors.. What the F**K do I do people? Losing my head here! And yeah, I'm powering it at 12 volts, tried 5. Output is always 3-6 volts. Thank you for any help provided! Imbanon --You received this message because you are subscribed to the Google Groups "neonixie-l" group.To post to this group, send an email to [email protected].To unsubscribe from this group, send email to neonixie-l [email protected]. For more options, visit this group at http://groups.google.com/ group/neonixie-l?hl=en-GB.
 JS Design 54 Brambledown Road Wallington Surrey SM6 0TF T+F +44 (0)20 8773 4779 www.jsdesign.co.uk -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
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