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 #76
Joined: Thu Feb 09 2006, 10:04AM
Location: Hemer, Germany
Posts: 458
within the last few days i experimented a lot with some useful plugins for sstcs and drsstcs and i really dont like stacking lots of ucc driver ics together to drive a fullbridge in cw so i decided to build a discrete driver instead and came up with a really good design less expensive and much more powerful than 2 pairs of ucc drivers
heres the shematic
then i tried to build a stand alone drsstc driver without using a single ic by adding an "enable" to the driver,. the funniest is, this thing works wondeful, not tested on a real drsstc but from the waveforms it could work
heres a pic showing the interrupted signal measured on one secondary winding of an 1:2:2 gdt voltage is 10V/div and frequency is 120khz
the transistor preamp can take any ttl signal to drive the bridge of an p/n channel mosfet, . for a simple cw feedback sstc its possible to add a feedback transformer on the preamp , the preamp and the mosfet bridge act like a schmitt trigger and converts a sinusodial input to a nice squarewave to drive the gdt. maybe someone is interested
Registered Member #89
Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145
I experimented vith various kinds of 'discrete' drives and decided that it is hard to beat power and speed of UCC's. Mosfets you use even if they are small and relatively fast again need something better than simple bipolar totem pole to acheive full-speed turnon.
I even used 7667's to drive mosfets directly and it still wasn't good.
You didn't state most imoprtant tihngs, what gate capacitance are you driving, and what are exact fall and rise times you get? You will need to zoom the waveform a bit to see that clearly.
I somehow doubt you can beat power of UCCs that way, exscept it may be a solution for bricks etc. at lower frequencies..
Registered Member #76
Joined: Thu Feb 09 2006, 10:04AM
Location: Hemer, Germany
Posts: 458
i build a testfullbridge with the to247 40n60s and a single gdt driven with 120khz cw and the output signal is the best ive ever seen on a fullbridge. the driver draws around 0,7A at 20volts, how much uccs do you want to stack together to drive such a bridge?. tommorow i can take a few pics, but i doubt my scope is good enough to measure the fall and rise times. for testing i connected a toshiba brick igbt with 40nF gate capacitance and with this setup i could drive it up to 100khz with a gdt without much trouble, . without a gdt ala high side switching i could turn it up to 120khz.
Registered Member #15
Joined: Thu Feb 02 2006, 01:11PM
Location:
Posts: 3068
Looks good, although unless you are using your discrete driver to power some of those super large CM300 or CM600 (or similar) bricks, you really don't need something as complicated as that.
For example, i use just single UCC2732x type MOSFET drivers for driving in large IGBTs such as the Fairchild 40N60's, and i don't parallel them either for a half-bridge. Even when using the small surface mount versions of these chips, they don't even get warm.
Registered Member #76
Joined: Thu Feb 09 2006, 10:04AM
Location: Hemer, Germany
Posts: 458
i wanted to use the discrete driver for a huge sstc i´ll build and that thing must work in cw so i think this discrete driver is the right choice. cause i use this bipolar transistor preamp i can use a optocoupler to connect the HF signal and i only need a single insulated supply voltage. and i have some huge fuji igbts left with 38nf gate capacitance and some toshiba and eupec igbt bricks. maybe i can use the circuit for a simple feedback controlled smps with a feedback winding driving the bipolar preamp, many useful applications for this thing
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.
Powerful discrete GDT Driver
