LTspiceXVII amusement

I was doodling with JL's HV bandaid circuit, and LTspice came up with something, um, unusual. Check out the current through C1, and compare with that in R6 and R1.

Cheers

Phil Hobbs

Version 4 SHEET 1 880 680 WIRE 256 -256 -112 -256 WIRE 352 -256 256 -256 WIRE 464 -256 432 -256 WIRE 464 -240 464 -256 WIRE 400 -192 144 -192 WIRE 144 -160 144 -192 WIRE 464 -112 464 -144 WIRE 464 -112 368 -112 WIRE 592 -112 464 -112 WIRE 368 -96 368 -112 WIRE 464 -96 464 -112 WIRE -112 -48 -112 -256 WIRE 144 -48 144 -80 WIRE 144 -48 -112 -48 WIRE 256 -48 256 -256 WIRE 368 0 368 -16 WIRE 464 0 464 -16 WIRE 464 0 368 0 WIRE 464 32 464 0 WIRE 592 48 592 -112 WIRE 256 80 256 32 WIRE 256 80 192 80 WIRE 400 80 256 80 WIRE -112 112 -112 -48 WIRE 192 144 192 80 WIRE 256 144 256 80 WIRE 464 176 464 128 WIRE 464 176 368 176 WIRE 368 192 368 176 WIRE 464 192 464 176 WIRE -112 224 -112 192 WIRE 192 240 192 208 WIRE 256 240 256 224 WIRE 256 240 192 240 WIRE 256 256 256 240 WIRE 368 288 368 272 WIRE 464 288 464 272 WIRE 464 288 368 288 WIRE 592 288 592 112 WIRE 592 288 464 288 WIRE 464 320 464 288 WIRE 464 416 464 400 WIRE 480 416 464 416 FLAG -112 224 0 FLAG 464 416 0 FLAG 256 256 0 SYMBOL voltage -112 96 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V1 SYMATTR Value 120 SYMBOL res 448 304 R0 SYMATTR InstName R1 SYMATTR Value 10k SYMBOL pnp 400 128 M180 SYMATTR InstName Q1 SYMATTR Value 2N5401 SYMBOL pnp 400 -144 M180 SYMATTR InstName Q2 SYMATTR Value 2N2907 SYMBOL cap 576 48 R0 SYMATTR InstName C1 SYMATTR Value 1? SYMBOL ind 448 -112 R0 SYMATTR InstName L1 SYMATTR Value 1? SYMBOL res 352 -112 R0 SYMATTR InstName R2 SYMATTR Value 1000 SYMBOL ind 448 176 R0 WINDOW 0 56 34 Left 2 WINDOW 3 56 72 Left 2 SYMATTR InstName L2 SYMATTR Value 1? SYMBOL res 352 176 R0 SYMATTR InstName R3 SYMATTR Value 1000 SYMBOL res 240 -64 R0 SYMATTR InstName R4 SYMATTR Value 5k SYMBOL res 240 128 R0 SYMATTR InstName R5 SYMATTR Value 100k SYMBOL cap 176 144 R0 SYMATTR InstName C2 SYMATTR Value 1? SYMBOL voltage 144 -176 R0 WINDOW 3 -231 -45 Left 2 WINDOW 123 24 44 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value PULSE(-2 -2.1 1u 1n 1n 10u) SYMATTR Value2 AC 1 SYMBOL res 448 -272 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 1k TEXT 88 328 Left 2 !.tran 20u

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
https://hobbs-eo.com
Reply to
Phil Hobbs
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I haven't had time to run it, but I had in mind that the load would be more like 60 ohms, not 10K. I only want a volt or two swing at the load.

LT Spice does have FB models.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

Incidentally I didn't think it was possible to make an uglier/clunkier UI than LTSpice IV but they somehow managed to pull it off.

Reply to
bitrex

Your symbols do not make it through. What are the values of

SYMATTR InstName C1 SYMATTR Value 1?

SYMATTR InstName L1 SYMATTR Value 1?

SYMATTR InstName L2 SYMATTR Value 1?

SYMATTR InstName C2 SYMATTR Value 1?

You can avoid this problem by turning off symbols in LTspice.

Reply to
Steve Wilson

Approximately. Looks that they are 4-component models, not very good. Also, they're linear, which is another popular lie (mind, not that I've ever seen a nonlinear model besides my own).

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And that's one of the better ferrite beads, actually. Fairly high Q at low frequency, at least if you believe the measurement. A lot of 'em get really smooshy at low frequencies, a maximum Q of maybe 10, and you need two or three stages of R+L in parallel to reasonably fit it.

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: https://www.seventransistorlabs.com/
Reply to
Tim Williams

It's not bad at all, and I have seen worse. You can make pretty schematics if you really want to.

I do keep confusing the snip and run icons, but my vision is pretty bad.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

It might just be all the fog!

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Reply to
Cursitor Doom

Two parallel LRs in series gets reasonably close. But I wasn't intending this as a criticism of your gizmo, it was just amusing that the bottom stage ran at >10x the current of the top stage.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
https://hobbs-eo.com
Reply to
Phil Hobbs

All 1u. I have symbols turned off in LTspice 4 but hadn't done so in 17 yet.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
https://hobbs-eo.com
Reply to
Phil Hobbs

Oh, go ahead and criticize. The majority of my ideas are goofy. That's what ideas are for. The trick is to just not put the goofy ones into production.

What I really need is a floating, programmable battery.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

I live about three miles from work. There's never fog here at work, and we get giant fog rivers at home. We like the fog.

I just have rotten vision, and I never learned to type.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com
Reply to
John Larkin

Thanks

Reply to
Steve Wilson

Twice. The Mac version is 10x uglier, which seems incredible. I'm not sure how it was even possible.

Reply to
Clifford Heath

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