If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #989
Joined: Sat Sept 08 2007, 02:15AM
Location: São Paulo, Brazil
Posts: 476
As I know the pin 2 and 6 of the 555 must be wired together to work in that mode. the center tap of the bridge are wired direct with the center tap of the caps (the primary coil is shorted), the led is in "reverse" position :P
The GDT is 1:1:1? If not, put back-to-back 15V zeners on the gates. The GDT cap must be a little higher than 100nF, I have experienced a few problems with only 100nF, use three or four 100nF caps in parallel or a 470nF one.
Hmm, I hope I didnt forgot anything. I dont like to correct other people schematic, but that is what you asking isnt it? :P
(Someone with higher experience correct me if I am wrong on something)
Registered Member #195
Joined: Fri Feb 17 2006, 08:27PM
Location: Berkeley, ca.
Posts: 1111
if you use a d-type flipflop you can enshure that your fets won't turn on at the wrong time. disconect the 555s pin 3 from the ucc37322,1 pin3 and connect it to the D input. Connect the junction that connects at the cd40106pin4 to the clock. And finaly reconnect boath pin 3's of the ucc's to the Q out put
what should happen is the the gating will be syncronised with input train
Registered Member #33
Joined: Sat Feb 04 2006, 01:31PM
Location: Norway
Posts: 971
I have not seen anyone use turn-off synchronization in conventional SSTCs before.
Are you going to have the interrupter on the same board as the rest of the electronics? In that case, why not make it out of a gate from the 40106 instead of using a 555?
This is just an opinion, but I prefer running SSTCs from halfwave rectified mains, not interrupted, as they tend to allow a lot higher coupling without flashover, and therefore longer sparks from a given coil, in addition to the sparks looking more interesting and less of the screeching sound that interrupted SSTCs make.
Registered Member #989
Joined: Sat Sept 08 2007, 02:15AM
Location: São Paulo, Brazil
Posts: 476
I never had any problems with unsyncronized interrupter on SSTC's, because even if the mosfets turn off on half of the cycle, the current doest get the peak rate of the mosfet, so I *think* it maybe not a problem. As I said, I never had any problems with that.
Banned on 3/17/2009. Registered Member #487
Joined: Sun Jul 09 2006, 01:22AM
Location:
Posts: 617
You could eliminate the zeners and shottkys on the secondary base input. Interrupted sstc's are only screechy if you run them at a high frequency with a low duty cycle. I use 10uF on my GDT primary.
Registered Member #989
Joined: Sat Sept 08 2007, 02:15AM
Location: São Paulo, Brazil
Posts: 476
Yeah, biggest GDT cap as possible, I used 1uF for a fullbridge of IGBTs (that have higher gate capacitance than that IRFP260) and worked fine. So choose what you can find =D
Registered Member #540
Joined: Mon Feb 19 2007, 07:49PM
Location: MIT
Posts: 969
I would bias the input of the NOT gate with some resistors (pin one in your case). I have seen 10k used for bias resistors so I would think that they would be fine.
Registered Member #1157
Joined: Thu Dec 06 2007, 12:11PM
Location: Houston, TX
Posts: 307
Myke wrote ...
I would bias the input of the NOT gate with some resistors (pin one in your case). I have seen 10k used for bias resistors so I would think that they would be fine.
Why would I need to bias the input? There is already a resistor on the input of the not gate. Does it need to sink that much current?
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
Schematic submitted for review.
