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How to fix LTspice schematic

I made massive changes and have something working; used NPN/PNP pair as an inverting gate driver. In the process, i have found a classical multivibrator does not work: Version 4 SHEET 1 1444 1224 WIRE -480 624 -512 624 WIRE -368 624 -416 624 WIRE -288 624 -368 624 WIRE -144 624 -208 624 WIRE -512 672 -512 624 WIRE 0 720 -304 720 WIRE 0 752 0 720 WIRE -304 768 -304 720 WIRE -368 816 -368 624 WIRE -336 816 -368 816 WIRE -144 848 -144 624 WIRE -144 848 -192 848 WIRE -112 848 -144 848 WIRE 0 864 0 832 WIRE -496 880 -576 880 WIRE -368 880 -432 880 WIRE -336 880 -368 880 WIRE -576 912 -576 880 WIRE -304 944 -304 928 WIRE -16 944 -304 944 WIRE -16 976 -16 944 WIRE -16 1088 -16 1056 WIRE -576 1104 -576 992 WIRE -464 1104 -576 1104 WIRE -368 1104 -368 880 WIRE -368 1104 -384 1104 WIRE -288 1104 -368 1104 WIRE -144 1104 -144 848 WIRE -144 1104 -208 1104 WIRE -576 1152 -576 1104 FLAG -512 672 0 FLAG -576 1152 0 FLAG -16 1088 0 FLAG 0 864 0 FLAG -112 848 Vo SYMBOL voltage -16 1072 R180 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value 12V SYMBOL Opamps\\\\LT6011 -304 848 R0 SYMATTR InstName U2 SYMBOL voltage 0 736 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 12V SYMBOL res -192 608 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R1 SYMATTR Value 10K SYMBOL res -192 1088 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R2 SYMATTR Value 1m SYMBOL res -368 1088 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R3 SYMATTR Value 47 SYMBOL cap -416 608 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C1 SYMATTR Value 1µ SYMBOL cap -432 864 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C2 SYMATTR Value 0.1µ SYMBOL res -592 896 R0 SYMATTR InstName R4 SYMATTR Value 1e15 TEXT -98 650 Left 0 !.tran 0 10s 1U

Reply to
Robert Baer
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since

after

for

(1.2kV/(48M + 100K + 1K)) * 101K = 2.5V

Dunno - ask DNA (Genome)

... Johnny

Reply to
Johnny Boy

I just had a go at this - if you first place a line, then drag the end of it, it's not hard to make it 45 degrees instead of 90. (That's how the &#$()#$ it was done, I guess)

... Johnny

Reply to
Johnny Boy

I ment, where is that 2.5V reference?

Reply to
Robert Baer

Ahhh.... Thanks!

Reply to
Robert Baer

Trise/fall,

"SpiceLine"

Right, sorry, I misunderstood and thought that you meant from a feedback point of view. The 2.5V reference is the half-way point of the Vhigh and Vlow of the (first) inverter, A1. ie Vhigh=5V and Vlow=0V, so Vthresh =

2.5V. I'm surprised that Genome has deserted the thread, after putting so much time into the alternative schematic. Incidentally, my calculation was slightly out. If A3 is low, the 1K resistor is not in the equation. Not much difference, though, it's still near enogh to 2.5V of feedback at 1.2kV output.

... Johnny

Reply to
Johnny Boy

Yes, sorry.... my circuit is, sort of a load of bollocks. Looks cute on the surface but has certain intrinsic f*ck ups that you lot are seeing. They might be sorted out but I am guilty of being a half arse.

Now I was trying harder and then I thought bugger it.

Anyway, before that. You get your diagonals in the schematic editor by doing a left right left wire....

------- | | --------

OK right down right... Then you drag one of the rights and the down becomes a diagonal.

As to my original bird bath, one of the problems you have got is you are thinking you are driving your multiplier with a 'flyback' converter but they like the secondary to be open circuit (blocked by a diode) when the primary switch is on. Unfortunately, with the multiplier as the load that doesn't happen.......

People do it and it 'works' but it's dirty. The Larkin knows about this.

DNA

Reply to
Genome

Yes!!!!!!!, me too.... ignore my other one.

DNA

Reply to
Genome

Oh my, never heard that one before. I did not know, but understand the "..like the secondary to be open circuit when the primary switch is on". But am a bit confused by that modifier "blocked by a diode". Would you be so kind as to explain for my edification? Now thru experimenting, i know that "heavy" loading has a profound effect on the flyback pulse amplitude, shape and width. But i do not remember seeing an effect on the current waveform when the switch (FET) is on (but i was not looking carefully either).

Reply to
Robert Baer

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