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Re: Flyback Driver PCBs
Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>
Once again...
There are zener diodes that are in seires with the mosfet gates, obviously
bringing the gate voltage down to 15v.
There is no schematic. It is a TL494 driving two gate drive ICs, a gate
drive transformer and a half bridge of whatever you want.
IF you insist on telling me over and over again how wrong I am, I suggest
you find something else to do, you're really not trying to be helpful but
rather antagonistic. And no one wants to hear about this.
Regards - Jim Mitchell
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, April 12, 2004 6:08 PM
Subject: Re: Flyback Driver PCBs
> Original poster: "Dan" <pbursa-at-cfl.rr-dot-com>
>
>
> ----- Original Message -----
> From: "Tesla list" <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Monday, April 12, 2004 2:51 PM
> Subject: Re: Flyback Driver PCBs
>
>
> > Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>
> >
> > Thats plenty impressive. The problem with Aron's flyback driver is
that
> it
> > is limited to 15v input. I had the same driver for a while but I was
> using
> > a TL494 so I could put up to 40v into it.
>
> No, it's not. The 555 is. Gates of mosfets shouldn't see more than 20
> volts. So TL494 -at- 40 V doesn't sound right( not to mention the fact that
> TL494 doesn't sink current.)
>
> > If you're saying you get 4" out of a single flyback at 25v you're
either
> > lying or not measuring right.
>
> Thats what I'm saying :-) Flyback # 8-598-998, four turns of primary and I
> AM measuring right
>
> > At 25v on the primary I can pull a 3" arc before my small flyback
(which
> has
> > a 1" diameter secondary) Starts to arc over internally.
>
> get better flyback :-)
>
> > This is similar to Steve's flyback driver except it uses a TL494 for
> better
> > control over the flyback with adjustable duty cycle.
> >
> > Once again, a switch is a switch. If the flyback is in resonance
you'll
> > get the same sparks on any half bridge in the world if you're driving
it
> at
> > the same voltage
>
> Really ? why is there so many different types of flybacks, then ?
>
>
> > Did I mention I wasn't running my flybacks in resonance when I was
pulling
> > these 3" arcs. I just set the frequency around 30KHz and I'm sure if
the
> > flyback was in resonance it would perform much better.
> >
> > Once again, this isn't a thread to elaborate on my spark lengths. It
is
> to
> > ask whether there is interest for a flyback driver PCB.
>
> You didn't post any schematic and your description of output of the driver
> sounds rather un-exiting
> Regards - Vladan
>
> > ----- Original Message -----
> > From: "Tesla list" <tesla-at-pupman-dot-com>
> > To: <tesla-at-pupman-dot-com>
> > Sent: Monday, April 12, 2004 9:53 AM
> > Subject: Re: Flyback Driver PCBs
> >
> >
> > > Original poster: "Dan" <pbursa-at-cfl.rr-dot-com>
> > >
> > > two inches arc with halfbridge driver ? that's really not impresive.
> With
> > > HVguys simple flyback driver I can get 3-4 inches -at- 25V and Steve
Wards
> > half
> > > bridge driver does easy 5 inches -at- 60V.
> > > I suggest you work on your design a bit ;-)
> > > regards - Vladan
> > >
> > > ----- Original Message -----
> > > From: "Tesla list" <tesla-at-pupman-dot-com>
> > > To: <tesla-at-pupman-dot-com>
> > > Sent: Monday, April 12, 2004 2:01 AM
> > > Subject: Flyback Driver PCBs
> > >
> > >
> > > > Original poster: "Jim Mitchell" <electrontube-at-sbcglobal-dot-net>
> > > >
> > > > Hello List:
> > > >
> > > > After the recent sucsess of my SSTC boards, and my recent
> > experimentation
> > > > with a high powered flyback driver, I have decied I'd like to
have
> > some
> > > > flyback driver boards made.
> > > >
> > > > The boards would be custom 2 sided boards, utilizing a half
bridge
> of
> > > > MOSFETs or IGBTs, and a variable oscillator and gate drive
section.
> > This
> > > > would work wonders as a flyback driver and as a GP high frequency
> > > generator
> > > > for different experiments.
> > > >
> > > > The board would use a TL494 oscillator, that way the duty cycle
and
> > > > frequency would be variable.
> > > >
> > > > I recently built an identical flyback driver and it works very
good,
> I
> > am
> > > > able to drive flybacks with half wave AC up to 150v or until they
> start
> > to
> > > > break down from overvoltage (about 50v in) and I have been able
to
> get
> > 2"
> > > > sparks from a single small flyback (a new style DC one).
> > > >
> > > > Anyway if there is any interest in these please let me know and I
> will
> > > send
> > > > word to have them made. I have already designed the board and
> things
> > seem
> > > > to look good.
> > > >
> > > > Regards - Jim Mitchell
> > > >
> > > >
> > >
> > >
> >
> >
>