For schematic of my "controller" see http://www.oil4lessllc.org/Misc/ .
Some responders in the past indicated that the source had to be pulled down to ground for the dratted IR2118 to work properly.
Note in my case i need the output to be adjustable from somewhere near ground (50V will do) to somewhere near supply (120V), and that voltage have little ripple (say under 10% or 10V - whichever is reasonable for supply to bottom of flyback in TV.
As shown, i do not get an adjustable voltage, and it is fairly low.
Clues please to get this to work (or an alternate that is cheeep.
Thanks.
On 12 Nov., 21:57, Robert Baer <robertb...@localnet.com> wrote:
> For schematic of my "controller" seehttp://www.oil4lessllc.org/Misc/.
> Some responders in the past indicated that the source had to be
> pulled down to ground for the dratted IR2118 to work properly.
> Note in my case i need the output to be adjustable from somewhere
> near ground (50V will do) to somewhere near supply (120V), and that
> voltage have little ripple (say under 10% or 10V - whichever is
> reasonable for supply to bottom of flyback in TV.
> As shown, i do not get an adjustable voltage, and it is fairly low.
> Clues please to get this to work (or an alternate that is cheeep.
> Thanks.
what are you trying to do, could you make a simple schematic?
langw...@fonz.dk wrote:
> On 12 Nov., 21:57, Robert Baer<robertb...@localnet.com> wrote:
>> For schematic of my "controller" seehttp://www.oil4lessllc.org/Misc/.
>> Some responders in the past indicated that the source had to be
>> pulled down to ground for the dratted IR2118 to work properly.
>> Note in my case i need the output to be adjustable from somewhere
>> near ground (50V will do) to somewhere near supply (120V), and that
>> voltage have little ripple (say under 10% or 10V - whichever is
>> reasonable for supply to bottom of flyback in TV.
>> As shown, i do not get an adjustable voltage, and it is fairly low.
>> Clues please to get this to work (or an alternate that is cheeep.
>> Thanks.
> what are you trying to do, could you make a simple schematic?
On a sunny day (Mon, 12 Nov 2012 12:57:35 -0800) it happened Robert Baer
<robertb...@localnet.com> wrote in <9pdos.3348$s44.1...@newsfe11.iad>:
> For schematic of my "controller" see http://www.oil4lessllc.org/Misc/ .
> Some responders in the past indicated that the source had to be >pulled down to ground for the dratted IR2118 to work properly.
> Note in my case i need the output to be adjustable from somewhere >near ground (50V will do) to somewhere near supply (120V), and that >voltage have little ripple (say under 10% or 10V - whichever is >reasonable for supply to bottom of flyback in TV.
> As shown, i do not get an adjustable voltage, and it is fairly low.
> Clues please to get this to work (or an alternate that is cheeep.
> Thanks.
You need to read up on switcth mode design basics.
At teh very basics you need to put a bit of charge into the output
capacitor every cycle, that requires an inductor in series with the switch.
This drawing you show makes no sense.
You would also need a flyback diode in the simplest design.
+ --- switch --------L --------
| |
in --- C load
/ \ |
-- |
| |
-------------------------------
There are many more ways and many configuration possible, yours is not one of them :-)
> langw...@fonz.dk wrote:
> > On 12 Nov., 21:57, Robert Baer<robertb...@localnet.com> wrote:
> >> For schematic of my "controller" seehttp://www.oil4lessllc.org/Misc/.
> >> Some responders in the past indicated that the source had to be
> >> pulled down to ground for the dratted IR2118 to work properly.
> >> Note in my case i need the output to be adjustable from somewhere
> >> near ground (50V will do) to somewhere near supply (120V), and that
> >> voltage have little ripple (say under 10% or 10V - whichever is
> >> reasonable for supply to bottom of flyback in TV.
> >> As shown, i do not get an adjustable voltage, and it is fairly low.
> >> Clues please to get this to work (or an alternate that is cheeep.
> >> Thanks.
> > what are you trying to do, could you make a simple schematic?
> > -Lasse
> Please READ the first line..
That is for you "controller", I mean a schematic of the system, the
supplies,
the load etc.
when you say bottom of flyback, I'm imagining you need a supply that
can sink
current?
Robert Baer wrote:
> For schematic of my "controller" see http://www.oil4lessllc.org/Misc/ .
> Some responders in the past indicated that the source had to be pulled
> down to ground for the dratted IR2118 to work properly.
> Note in my case i need the output to be adjustable from somewhere near
> ground (50V will do) to somewhere near supply (120V), and that voltage
> have little ripple (say under 10% or 10V - whichever is reasonable for
> supply to bottom of flyback in TV.
> As shown, i do not get an adjustable voltage, and it is fairly low.
> Clues please to get this to work (or an alternate that is cheeep.
> Thanks.
Full manual for the TV set, and extracted schematic, with selected info now added to http://www.oil4lessllc.org/Misc/ .
I have added a pulse transformer..the IR2118 is now driving its primary, and a 1K added from Vs (pin 6) to ground lets it work nicely.
Still do not get adjustable range desired.
The pulse transformer used is the Murata 78601/2C (500uH) and does not "transmit" the full width of the pulse:
More inductance isn't the problem; you need one with a higher V.us flux rating.
In that particular series, they use Ferroxcube 3F3 cores, so a higher inductance will be consistent with higher flux, not just a higher permeability core.
> Robert Baer wrote:
>> For schematic of my "controller" see http://www.oil4lessllc.org/Misc/ .
>> Some responders in the past indicated that the source had to be pulled
>> down to ground for the dratted IR2118 to work properly.
>> Note in my case i need the output to be adjustable from somewhere near
>> ground (50V will do) to somewhere near supply (120V), and that voltage
>> have little ripple (say under 10% or 10V - whichever is reasonable for
>> supply to bottom of flyback in TV.
>> As shown, i do not get an adjustable voltage, and it is fairly low.
>> Clues please to get this to work (or an alternate that is cheeep.
>> Thanks.
> Full manual for the TV set, and extracted schematic, with selected > info now added to http://www.oil4lessllc.org/Misc/ .
> I have added a pulse transformer..the IR2118 is now driving its > primary, and a 1K added from Vs (pin 6) to ground lets it work nicely.
> Still do not get adjustable range desired.
> The pulse transformer used is the Murata 78601/2C (500uH) and does not > "transmit" the full width of the pulse:
Tim Williams wrote:
> More inductance isn't the problem; you need one with a higher V.us flux
> rating.
> In that particular series, they use Ferroxcube 3F3 cores, so a higher
> inductance will be consistent with higher flux, not just a higher
> permeability core.
