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Registered Member #1596
Joined: Fri Jul 18 2008, 08:43PM
Location: USA
Posts: 65
Harry wrote ...
Chinese manufacturers selling on ebay are able to supply a wide range of high voltage diodes at very competitive prices.
I have bought diodes and HV capacitors directly from China and found them both quick and reliable.
Those are not fast recovery ones, they are good for nst, but if you use SMPS, they will overheat and fry ;) Their recovery is in micro seconds range. From my experience, even 75ns 2A diodes heat up considerably at 0.2A @ 100kHz
There are also some ultrafast 1-2A up to 1.2kV SMT type diodes (stth series) available from moser, digikey etc. I found out that a bridge from smt diodes is much faster to solder onto PCB vs twisting and soldering thruhole diodes into strings.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
baleworker wrote ...
Harry wrote ...
Chinese manufacturers selling on ebay are able to supply a wide range of high voltage diodes at very competitive prices.
I have bought diodes and HV capacitors directly from China and found them both quick and reliable.
Those are not fast recovery ones, they are good for nst, but if you use SMPS, they will overheat and fry ;) Their recovery is in micro seconds range.
I couldn't find any HV diodes from the seller I recommended whose recovery speeds were in the uS range as you suggest - most are either 150nS or 100nS - which would usually be called 'fast recovery.'
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3141
I too have bought and used hv diodes from China via eBay, (30kV 30mA and 20kV 10mA, both types 150ns) so far no problems, I haven't measured Trr but I use them with flyback transformers and they're good.
One thing ... The diodes are quite short and will flash-over below rated voltage if not in oil/wax/epoxy etc.
Delivery times are fantastic.
However, if the British Pound keeps dropping like it is, then Chinese will start buying from us!
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