Hi, first: interesting & very useful webpage ! (recognized your nickname). Appreciate people who share information like that.
Increasing frequency will only result in maxing out duty cycles. Not sure if I tested the RLB on >= 60kHz yet though, I'll give it a go later. What frequency are you at, approximately ? Assuming you're using the MC34063, I'm not sure how the PWM scheme looks on that one. Have you tried peeling off the outer shrink tube on the inductor ? At first I didn't think there was any significant heat, until I realized the shrink tube was messing with me. Anyways, I found some nice off-the shelf transformers which looks very promising in simulation, so I'm heading for flyback. Slightly more expensive though, but not a concern for me. - Oyvind On Monday, November 12, 2018 at 9:45:51 PM UTC+1, threeneurons wrote: > > I think your doing something wrong. I use the RLB9012-101KL routinely, and > get twice the output current (~35mA @ 180V), while the coil gets warm, but > still within reason. I'd suggest that you increase your switching > frequency. I suspect you're well into saturation. > > On Tuesday, November 6, 2018 at 12:12:29 AM UTC-8, Oyvind wrote: >> >> Hi, >> >> I have been experimenting a bit with single inductor supplies. I built >> one myself based on TPS40210, and tried a couple of others too. >> >> Common for all, is that the inductor gets quite hot when running them on >> a 10K dummy load @180V. >> >> So, for 6 IN-14 tubes on 1.5 mA each, they work just fine, but not much >> more than that. >> >> I tried various inductors, with fairly high amp ratings: >> >> >> - shielded SMD ones have most pronounced. That is, I can hold my finger >> on it, but just barely. >> - radial THT, souch as Bourns RLB9012-101KL. When peeling off the outer >> coating, the heat is obvious >> - toroids with low ohms / high amps. These gives best result, but gets >> "luke warm". >> >> I'm thinking that having a supply like that inside a casing would not be >> good in the long run. I am aiming for non-multiplexed.. >> >> Not sure how to remedy this (snubber or similar ?), perhaps this topology >> isn't the most ideal. >> >> >> What's your experiences here ? >> >> -- 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/dcb1f4d6-c436-4118-aa95-66ea3f6278a4%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
