Low noise, high bias voltage on picoAmp TIA's input, howto?

On Friday, May 28, 2021 at 11:26:41 PM UTC+10, Bill Sloman wrote:

Here's a more conventional LT Spice model of a MOSFet driven inverter.

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208 608 208 WIRE 848 208 784 208 WIRE 896 208 848 208 WIRE 1040 208 960 208 WIRE 1232 208 1120 208 WIRE 1440 208 1232 208 WIRE -624 288 -624 208 WIRE -400 288 -624 288 WIRE -208 288 -400 288 WIRE 560 288 -128 288 WIRE 720 288 560 288 WIRE 848 288 848 208 WIRE 848 288 784 288 WIRE -704 352 -704 48 WIRE 320 368 320 48 WIRE 1440 384 1440 208 WIRE -592 432 -656 432 WIRE -304 432 -304 -256 WIRE -304 432 -512 432 WIRE 0 448 0 -304 WIRE 112 448 112 -256 WIRE 160 448 112 448 WIRE 272 448 240 448 WIRE 1232 480 1232 208 WIRE -304 560 -304 432 WIRE 112 576 112 448 WIRE -1312 736 -1312 -32 WIRE -1088 736 -1088 208 WIRE -1088 736 -1312 736 WIRE -704 736 -704 448 WIRE -704 736 -1088 736 WIRE -400 736 -400 288 WIRE -400 736 -704 736 WIRE -304 736 -304 640 WIRE -304 736 -400 736 WIRE 0 736 0 528 WIRE 0 736 -304 736 WIRE 112 736 112 656 WIRE 112 736 0 736 WIRE 320 736 320 464 WIRE 320 736 112 736 WIRE 1232 736 1232 544 WIRE 1232 736 320 736 WIRE 1312 736 1232 736 WIRE 1440 736 1440 464 WIRE 1440 736 1312 736 WIRE 1472 736 1440 736 WIRE 1552 736 1472 736 WIRE -1312 768 -1312 736 WIRE 1312 784 1312 736 WIRE 1472 832 1472 736 WIRE 608 864 608 208 WIRE 752 864 608 864 WIRE 944 864 816 864 WIRE 560 992 560 288 WIRE 752 992 560 992 WIRE 944 992 944 864 WIRE 944 992 816 992 WIRE 992 992 944 992 WIRE 1088 992 1056 992 WIRE 1312 992 1312 848 WIRE 1312 992 1168 992 WIRE 1472 992 1472 912 WIRE 1472 992 1312 992 FLAG -1312 768 0 FLAG -544 -16 Vct FLAG -640 -112 tank- FLAG -128 -112 tank+ DATAFLAG 1328 208 "" SYMBOL ind2 -688 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -384 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 132 Left 0 SYMATTR SpiceLine Rser=0.001 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 -192 -320 M90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 780n SYMATTR Type ind SYMATTR SpiceLine Rser=0.004 Cpar=1pF SYMBOL res -304 -592 R0 SYMATTR InstName R14 SYMATTR Value 2k2 SYMBOL res 192 448 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 22 SYMBOL nmos 272 368 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 352 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV SYMBOL res -560 432 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 22 SYMBOL ind2 -960 -336 R0 SYMATTR InstName L6 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 720 224 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 720 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 816 848 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 816 976 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1216 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1296 784 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL FerriteBead 928 208 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L7 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL FerriteBead 1024 992 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L8 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p mfg="Würth Elektronik" pn="7427501 WE-UKW 40060" SYMBOL res 1440 416 R0 SYMATTR InstName R4 SYMATTR Value 820k SYMBOL res 1472 864 R0 SYMATTR InstName R5 SYMATTR Value 820k SYMBOL res 1136 992 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 1k SYMBOL res 1088 208 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R7 SYMATTR Value 1k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 100nF SYMBOL pnp -240 -256 R180 SYMATTR InstName Q1 SYMBOL pnp 48 -256 M180 SYMATTR InstName Q2 SYMBOL res -304 592 R0 SYMATTR InstName R3 SYMATTR Value 1k5 SYMBOL res 112 608 R0 WINDOW 3 13 26 Left 2 SYMATTR Value 1k5 SYMATTR InstName R9 SYMBOL res -32 -560 R0 SYMATTR InstName R10 SYMATTR Value 11k SYMBOL res 0 480 R0 SYMATTR InstName R11 SYMATTR Value 13k SYMBOL cap 144 -576 R0 SYMATTR InstName C5 SYMATTR Value 10n SYMBOL FerriteBead -944 -144 R180 SYMATTR InstName L3 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL ind2 -544 224 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -224 304 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -2 57 VBottom 2 SYMATTR InstName L9 SYMATTR Value 5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p TEXT -1232 792 Left 2 !.tran 0 10m 0m 100n TEXT -1232 856 Left 2 !K1 L1 L2 L3 L4 L5 0.99

Seems to work. Startup is messy. The MOSFet was picked from what LT Spice offered - it isn't all that cheap. The transformer is what Timo seems to have used, but I haven't worked out wire sizes and layering. The single turn winding - L5 - would presumably be at the bottom pf the stack, tucked in a corner under the centre-tapped primary, which I'd probably wind as as 15 turns of twisted pair. The secondaries are 80 turns each, which might be one layer each of 0.1mm wire - maybe 0.6mm with there layers of 0.06mm tape - but you still have 1.6 mm of height for the primaries, which should be plenty. Two layer secondaries might work too.

Bill Sloman

Hi Bill,

Excuse for the delay, please!

The simulation run always better without ferrites at the end, the inductance produced ringing.

Yes, it should! Because the load changes at this time.

I fiddled around with some vriations of the FET's gate control. All ended up in a more complicated but not necessarily "smoother" working circuits. The startup of the FET-based oscillator is much faster at the cost of a huge overshoot and much higher startup currents.

Wer are "lucky" to have the "time" problem only. I am the only one working on the analog part of this (and a few other) projects. Mostly we have to deliver only a few modules/systems to our scientific customers. So the part costs are not the main issue in most cases.

Hmm, for sure? I don't know exactly. See

In my opinion the BJT based variant seems to be more robust, more simple and has a smoother startup. The latest simulations showed >80% overall efficiency at 250kHz except core losses, which haven't been simulated. The no load power consumption is safely below 500mW (partly below 250mW). After all I trust the simulation in principle (because the circuit behaved very similar on the bench) and will build up (wind the transformer) the latest version for tests.

Your last circuit runs the simulation promptly but does not start nor oscillate normally. One cycle in 2ms. At least on my PC (LTSpice17). Maybe, the LTSpice versions behave different?

Thank you! Cheers, Timo

Real circuits use ferrite beads to contain ringing.

That doesn't tie up with what was going on.

If you use a large inductor (as you did) start up does involve the centre-tap voltage going well above what you see when the circuit has settled down, and the inductor pulling the centre-tap below ground during start-up. With bipolar transistors this gets you into squegging, which persists. If you put a high voltage zener between the centre-tap and ground - something like 40V - it will cap the centre tap-voltage, when it goes over 38V, and divert the negative current to ground, and the start-up would be briefer and cleaner.

The messy start-up isn't a consequence of the FET drive.

Simulations aren't real life.

You may need to revise that opinion. The start-up isn't a problem with actual circuits I've worked with, unless it persists - when it is called squegging.

Baxandall's paper only refers to it in a footnote on page 752. I've run into it in real life, and the late Tony Williams had seen more of it than he liked. It's not problem that persists with MOSFet drive.

Starting oscillators in LTSpice is pest. Real circuits have enough asymmetry so they start up fast. Simulated circuits are much more symmetrical.

My circuit did take a few msec start, which is why I let the simulation run for 10msec to let it settle down. You can fiddle the initial conditions to get them to start faster, but that takes work and it's rarely worth the effort.

In fact what was going on was that the current though feed inductor L6 - went up to 12.6A before the oscillator started oscillating at all, and it started off at 7kHz, moving up to 100kHz with about a millisecond.

You power supply isn't going to deliver 12A and real components are different enough that the oscillation would have got going earlier.

You can eliminate interference in active ways:

Note that the IET published a book co-authored by Kibble called "Coaxial Electrical Circuits for Interference-free Measurements" which is still in print. It covers the information in Kibble's earlier book.

I've tweaked my simulation by adding 22R to the 24V source, which pulls the initial peak current through L6 down to less than an amp. I threw in a zener to limit the peak centre tap voltage, but added a ferrite bead to kill some very high frequency ringing which showed up on the capacitative current through the zener in regular operatoin.

Version 4 SHEET 1 1668 1056 WIRE -1232 -688 -1312 -688 WIRE -1088 -688 -1152 -688 WIRE -944 -688 -1088 -688 WIRE -304 -688 -944 -688 WIRE -32 -688 -304 -688 WIRE 160 -688 -32 -688 WIRE 1488 -688 160 -688 WIRE -304 -624 -304 -688 WIRE -32 -592 -32 -688 WIRE 160 -576 160 -688 WIRE -32 -464 -32 -512 WIRE 160 -464 160 -512 WIRE 160 -464 -32 -464 WIRE -304 -432 -304 -544 WIRE 112 -432 -304 -432 WIRE -304 -352 -304 -432 WIRE 112 -352 112 -432 WIRE -944 -320 -944 -688 WIRE -176 -304 -240 -304 WIRE -32 -304 -32 -464 WIRE -32 -304 -96 -304 WIRE 0 -304 -32 -304 WIRE 48 -304 0 -304 WIRE -944 -176 -944 -240 WIRE -1312 -112 -1312 -688 WIRE -640 -112 -704 -112 WIRE -448 -112 -640 -112 WIRE -128 -112 -384 -112 WIRE 320 -112 -128 -112 WIRE -944 -16 -944 -112 WIRE -544 -16 -944 -16 WIRE -384 -16 -544 -16 WIRE -704 48 -704 -112 WIRE -672 48 -704 48 WIRE -384 48 -384 -16 WIRE -384 48 -592 48 WIRE -240 48 -384 48 WIRE 320 48 320 -112 WIRE 320 48 -160 48 WIRE -1088 144 -1088 -688 WIRE -528 208 -624 208 WIRE 608 208 -448 208 WIRE 720 208 608 208 WIRE 848 208 784 208 WIRE 896 208 848 208 WIRE 1040 208 960 208 WIRE 1232 208 1120 208 WIRE 1440 208 1232 208 WIRE -624 288 -624 208 WIRE -400 288 -624 288 WIRE -208 288 -400 288 WIRE 560 288 -128 288 WIRE 720 288 560 288 WIRE 848 288 848 208 WIRE 848 288 784 288 WIRE -704 352 -704 48 WIRE 320 368 320 48 WIRE -944 384 -944 -16 WIRE 1440 384 1440 208 WIRE -592 432 -656 432 WIRE -304 432 -304 -256 WIRE -304 432 -512 432 WIRE 0 448 0 -304 WIRE 112 448 112 -256 WIRE 160 448 112 448 WIRE 272 448 240 448 WIRE 1232 480 1232 208 WIRE -944 512 -944 448 WIRE -304 560 -304 432 WIRE 112 576 112 448 WIRE -1312 736 -1312 -32 WIRE -1088 736 -1088 208 WIRE -1088 736 -1312 736 WIRE -944 736 -944 576 WIRE -944 736 -1088 736 WIRE -704 736 -704 448 WIRE -704 736 -944 736 WIRE -400 736 -400 288 WIRE -400 736 -704 736 WIRE -304 736 -304 640 WIRE -304 736 -400 736 WIRE 0 736 0 528 WIRE 0 736 -304 736 WIRE 112 736 112 656 WIRE 112 736 0 736 WIRE 320 736 320 464 WIRE 320 736 112 736 WIRE 1232 736 1232 544 WIRE 1232 736 320 736 WIRE 1312 736 1232 736 WIRE 1440 736 1440 464 WIRE 1440 736 1312 736 WIRE 1472 736 1440 736 WIRE 1552 736 1472 736 WIRE -1312 768 -1312 736 WIRE 1312 784 1312 736 WIRE 1472 832 1472 736 WIRE 608 864 608 208 WIRE 752 864 608 864 WIRE 944 864 816 864 WIRE 560 992 560 288 WIRE 752 992 560 992 WIRE 944 992 944 864 WIRE 944 992 816 992 WIRE 992 992 944 992 WIRE 1088 992 1056 992 WIRE 1312 992 1312 848 WIRE 1312 992 1168 992 WIRE 1472 992 1472 912 WIRE 1472 992 1312 992 FLAG -1312 768 0 FLAG -544 -16 Vct FLAG -640 -112 tank- FLAG -128 -112 tank+ DATAFLAG 1328 208 "" SYMBOL ind2 -688 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -384 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 132 Left 0 SYMATTR SpiceLine Rser=0.001 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 -192 -320 M90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 780n SYMATTR Type ind SYMATTR SpiceLine Rser=0.004 Cpar=1pF SYMBOL res -304 -592 R0 SYMATTR InstName R14 SYMATTR Value 2k2 SYMBOL res 192 448 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 22 SYMBOL nmos 272 368 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 352 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV SYMBOL res -560 432 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 22 SYMBOL ind2 -960 -336 R0 SYMATTR InstName L6 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 720 224 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 720 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 816 848 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 816 976 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1216 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1296 784 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL FerriteBead 928 208 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L7 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL FerriteBead 1024 992 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L8 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p mfg="Würth Elektronik" pn="7427501 WE-UKW 40060" SYMBOL res 1440 416 R0 SYMATTR InstName R4 SYMATTR Value 820k SYMBOL res 1472 864 R0 SYMATTR InstName R5 SYMATTR Value 820k SYMBOL res 1136 992 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 1k SYMBOL res 1088 208 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R7 SYMATTR Value 1k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 100nF SYMBOL pnp -240 -256 R180 SYMATTR InstName Q1 SYMBOL pnp 48 -256 M180 SYMATTR InstName Q2 SYMBOL res -304 592 R0 SYMATTR InstName R3 SYMATTR Value 1k5 SYMBOL res 112 608 R0 WINDOW 3 13 26 Left 2 SYMATTR Value 1k5 SYMATTR InstName R9 SYMBOL res -32 -560 R0 SYMATTR InstName R10 SYMATTR Value 11k SYMBOL res 0 480 R0 SYMATTR InstName R11 SYMATTR Value 13k SYMBOL cap 144 -576 R0 SYMATTR InstName C5 SYMATTR Value 10n SYMBOL FerriteBead -944 -144 R180 SYMATTR InstName L3 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL ind2 -544 224 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -224 304 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -2 57 VBottom 2 SYMATTR InstName L9 SYMATTR Value 5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL zener -928 448 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D5 SYMATTR Value 1N5371B SYMBOL FerriteBead -944 544 R180 SYMATTR InstName L10 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL res -1136 -704 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R8 SYMATTR Value 22 TEXT -1232 792 Left 2 !.tran 0 10m 0m 100n TEXT -1232 856 Left 2 !K1 L1 L2 L3 L4 L5 0.99

A Resonant DC-DC transformer with Zero Current Ripple

It costs money to see it. The Cuk converter from 1983

Am 12.06.21 um 11:19 schrieb Dmitriy Pshonkin:

It looks cute. I particularly like the idea of winding the input inductor and the output filter inductance on the same core - they are coping with the same series of half-sine wave voltages, after all. To paraphrase Thomas Huxley on Darwin's Theory of evolution, I do feel a bit stupid for not thinking of it for myself.

Here's a version of Timo's +/-200V inverter that incorporates the idea. It's not in the least ripple free - there's about 80mA of ripple on the roughly 12mA DC current through the inductor L6, but there's very little voltage ripple on the 200V output - some 200mV. The turns ratio had to be pushed up appreciably to get 200V DC out - the circuit isn't peak-clipping any more.

There is a significant 1.8MHz component in the ripple current - it should be possible to work out where this coming from and damp it down, but it's not worth the trouble on a Spice simulation, though it would be worth doing if it showed up on a real circuit.

Version 4 SHEET 1 1668 1056 WIRE -1216 -688 -1312 -688 WIRE -1088 -688 -1136 -688 WIRE -944 -688 -1088 -688 WIRE -304 -688 -944 -688 WIRE -32 -688 -304 -688 WIRE 160 -688 -32 -688 WIRE 1488 -688 160 -688 WIRE -304 -624 -304 -688 WIRE -32 -592 -32 -688 WIRE 160 -576 160 -688 WIRE -32 -464 -32 -512 WIRE 160 -464 160 -512 WIRE 160 -464 -32 -464 WIRE -304 -432 -304 -544 WIRE 112 -432 -304 -432 WIRE -304 -352 -304 -432 WIRE 112 -352 112 -432 WIRE -944 -320 -944 -688 WIRE -176 -304 -240 -304 WIRE -32 -304 -32 -464 WIRE -32 -304 -96 -304 WIRE 0 -304 -32 -304 WIRE 48 -304 0 -304 WIRE -944 -176 -944 -240 WIRE -1312 -112 -1312 -688 WIRE -640 -112 -704 -112 WIRE -448 -112 -640 -112 WIRE -128 -112 -384 -112 WIRE 320 -112 -128 -112 WIRE -944 -16 -944 -112 WIRE -544 -16 -944 -16 WIRE -384 -16 -544 -16 WIRE -704 48 -704 -112 WIRE -672 48 -704 48 WIRE -384 48 -384 -16 WIRE -384 48 -592 48 WIRE -240 48 -384 48 WIRE 320 48 320 -112 WIRE 320 48 -160 48 WIRE -1088 144 -1088 -688 WIRE -528 208 -624 208 WIRE 608 208 -448 208 WIRE 720 208 608 208 WIRE 848 208 784 208 WIRE 896 208 848 208 WIRE 1072 208 976 208 WIRE 1232 208 1136 208 WIRE 1440 208 1232 208 WIRE -624 288 -624 208 WIRE -400 288 -624 288 WIRE -208 288 -400 288 WIRE 560 288 -128 288 WIRE 720 288 560 288 WIRE 848 288 848 208 WIRE 848 288 784 288 WIRE -704 352 -704 48 WIRE 320 368 320 48 WIRE -944 384 -944 -16 WIRE 1440 384 1440 208 WIRE -592 432 -656 432 WIRE -304 432 -304 -256 WIRE -304 432 -512 432 WIRE 0 448 0 -304 WIRE 112 448 112 -256 WIRE 160 448 112 448 WIRE 272 448 240 448 WIRE 1232 480 1232 208 WIRE -944 512 -944 448 WIRE -304 560 -304 432 WIRE 112 576 112 448 WIRE -1312 736 -1312 -32 WIRE -1088 736 -1088 208 WIRE -1088 736 -1312 736 WIRE -944 736 -944 576 WIRE -944 736 -1088 736 WIRE -704 736 -704 448 WIRE -704 736 -944 736 WIRE -400 736 -400 288 WIRE -400 736 -704 736 WIRE -304 736 -304 640 WIRE -304 736 -400 736 WIRE 0 736 0 528 WIRE 0 736 -304 736 WIRE 112 736 112 656 WIRE 112 736 0 736 WIRE 320 736 320 464 WIRE 320 736 112 736 WIRE 1232 736 1232 544 WIRE 1232 736 320 736 WIRE 1312 736 1232 736 WIRE 1440 736 1440 464 WIRE 1440 736 1312 736 WIRE 1472 736 1440 736 WIRE 1552 736 1472 736 WIRE -1312 768 -1312 736 WIRE 1312 784 1312 736 WIRE 1472 832 1472 736 WIRE 608 864 608 208 WIRE 752 864 608 864 WIRE 944 864 816 864 WIRE 560 992 560 288 WIRE 752 992 560 992 WIRE 944 992 944 864 WIRE 944 992 816 992 WIRE 976 992 944 992 WIRE 1152 992 1056 992 WIRE 1312 992 1312 848 WIRE 1312 992 1216 992 WIRE 1472 992 1472 912 WIRE 1472 992 1312 992 FLAG -1312 768 0 FLAG -544 -16 Vct FLAG -640 -112 tank- FLAG -128 -112 tank+ SYMBOL ind2 -688 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -384 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL ind2 -192 -320 M90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 780n SYMATTR Type ind SYMATTR SpiceLine Rser=0.004 Cpar=1pF SYMBOL res -304 -592 R0 SYMATTR InstName R14 SYMATTR Value 2k2 SYMBOL res 192 448 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 22 SYMBOL nmos 272 368 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 352 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV1 SYMBOL res -560 432 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 22 SYMBOL ind2 -960 -336 R0 SYMATTR InstName L6 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 720 224 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 720 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 816 848 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 816 976 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1216 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1296 784 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL res 1440 416 R0 SYMATTR InstName R4 SYMATTR Value 820k SYMBOL res 1472 864 R0 SYMATTR InstName R5 SYMATTR Value 820k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 1µF SYMBOL pnp -240 -256 R180 SYMATTR InstName Q1 SYMBOL pnp 48 -256 M180 SYMATTR InstName Q2 SYMBOL res -304 592 R0 SYMATTR InstName R3 SYMATTR Value 1k5 SYMBOL res 112 608 R0 WINDOW 3 13 26 Left 2 SYMATTR Value 1k5 SYMATTR InstName R9 SYMBOL res -32 -560 R0 SYMATTR InstName R10 SYMATTR Value 11k SYMBOL res 0 480 R0 SYMATTR InstName R11 SYMATTR Value 13k SYMBOL cap 144 -576 R0 SYMATTR InstName C5 SYMATTR Value 10n SYMBOL FerriteBead -944 -144 R180 SYMATTR InstName L3 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL ind2 -544 224 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 5.5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -224 304 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -2 57 VBottom 2 SYMATTR InstName L9 SYMATTR Value 5.5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL zener -928 448 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D5 SYMATTR Value 1N5371B SYMBOL FerriteBead -944 544 R180 SYMATTR InstName L10 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL res -1168 -688 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R8 SYMATTR Value 22 SYMBOL ind2 992 192 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L7 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=1p SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 44 Left 2 SYMATTR SpiceLine Rser=1 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 1072 976 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L8 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=1p SYMBOL FerriteBead 1104 208 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L11 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" SYMBOL FerriteBead 1184 992 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L12 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" TEXT -1232 792 Left 2 !.tran 0 10m 0m 100n TEXT -1232 856 Left 2 !K1 L1 L2 L3 L4 L5 0.99 TEXT -1312 -752 Left 2 !.model Si3440DV1 VDMOS(Rg=3 Vto=3.6 Rd=150m Rs=112.5m Rb=188m Kp=50 Cgdmax=.2n Cgdmin=.02n Cgs=.2n Cjo=.05n Is=11p ksubthres=.1 mfg=Siliconix Vds=150 Ron=375m Qg=5.4n) TEXT -856 792 Left 2 !.ic I(l6=15m I(L1=15m)) TEXT -848 856 Left 2 !K2 L6 L7 L8 0.99

Good job. High voltage linear regulated source.

Thank you guys, fro all your valaubel hints! I do not have enough time to answer something useful in the moment. Nevertheless I try to understand and "replay" all the ideas, especially the coupled inductors one, which looks very interesting. Unfortunately I am very bad in math, so I have to "guess" the right Lin/Lf values out of the paper. My version of the HV linear regulator for Bias seems to be okay, an AC simulation shows up to 100dB ripple rejection, I didn't measure it on the bench until now. It does not need to have high upper frequency corner. The amplitude response of 1Hz max. is enough for this application. See 20210531_FAMEIO_SuperSIMS-MV40-Ersatz_S44.pdf in the actualised link

Works fine for me. I updated LT Spice 17 a couple weeks ago. If you've done it more recently it may not be quite the same environment.

My start-up is still pretty horrible - Vtank peaks at 128V at about 12 usec, and I(6) at 1.34A at about 7.5usec. Regular oscillation sets in at about 56usec and it has more or less settled down by 500usec.

Oops. Not such a good job after all. I should have flipped L8 though 180 degrees when I originally cut and pasted it from L7.

Woke up in the middle of the night wondering whether I'd bother to do it. and when I checked. I hadn't.

I've done it here. Doesn't seem to have made much difference to the waveforms that I'd bothered to look at, which doesn't say anything good about my attention to detail

Version 4 SHEET 1 1668 1056 WIRE -1216 -688 -1312 -688 WIRE -1088 -688 -1136 -688 WIRE -944 -688 -1088 -688 WIRE -304 -688 -944 -688 WIRE -32 -688 -304 -688 WIRE 160 -688 -32 -688 WIRE 1488 -688 160 -688 WIRE -304 -624 -304 -688 WIRE -32 -592 -32 -688 WIRE 160 -576 160 -688 WIRE -32 -464 -32 -512 WIRE 160 -464 160 -512 WIRE 160 -464 -32 -464 WIRE -304 -432 -304 -544 WIRE 112 -432 -304 -432 WIRE -304 -352 -304 -432 WIRE 112 -352 112 -432 WIRE -944 -320 -944 -688 WIRE -176 -304 -240 -304 WIRE -32 -304 -32 -464 WIRE -32 -304 -96 -304 WIRE 0 -304 -32 -304 WIRE 48 -304 0 -304 WIRE -944 -176 -944 -240 WIRE -1312 -112 -1312 -688 WIRE -640 -112 -704 -112 WIRE -448 -112 -640 -112 WIRE -128 -112 -384 -112 WIRE 320 -112 -128 -112 WIRE -944 -16 -944 -112 WIRE -544 -16 -944 -16 WIRE -384 -16 -544 -16 WIRE -704 48 -704 -112 WIRE -672 48 -704 48 WIRE -384 48 -384 -16 WIRE -384 48 -592 48 WIRE -240 48 -384 48 WIRE 320 48 320 -112 WIRE 320 48 -160 48 WIRE -1088 144 -1088 -688 WIRE -528 208 -624 208 WIRE 608 208 -448 208 WIRE 720 208 608 208 WIRE 848 208 784 208 WIRE 896 208 848 208 WIRE 1072 208 976 208 WIRE 1232 208 1136 208 WIRE 1440 208 1232 208 WIRE -624 288 -624 208 WIRE -400 288 -624 288 WIRE -208 288 -400 288 WIRE 560 288 -128 288 WIRE 720 288 560 288 WIRE 848 288 848 208 WIRE 848 288 784 288 WIRE -704 352 -704 48 WIRE 320 368 320 48 WIRE -944 384 -944 -16 WIRE 1440 384 1440 208 WIRE -592 432 -656 432 WIRE -304 432 -304 -256 WIRE -304 432 -512 432 WIRE 0 448 0 -304 WIRE 112 448 112 -256 WIRE 160 448 112 448 WIRE 272 448 240 448 WIRE 1232 480 1232 208 WIRE -944 512 -944 448 WIRE -304 560 -304 432 WIRE 112 576 112 448 WIRE -1312 736 -1312 -32 WIRE -1088 736 -1088 208 WIRE -1088 736 -1312 736 WIRE -944 736 -944 576 WIRE -944 736 -1088 736 WIRE -704 736 -704 448 WIRE -704 736 -944 736 WIRE -400 736 -400 288 WIRE -400 736 -704 736 WIRE -304 736 -304 640 WIRE -304 736 -400 736 WIRE 0 736 0 528 WIRE 0 736 -304 736 WIRE 112 736 112 656 WIRE 112 736 0 736 WIRE 320 736 320 464 WIRE 320 736 112 736 WIRE 1232 736 1232 544 WIRE 1232 736 320 736 WIRE 1312 736 1232 736 WIRE 1440 736 1440 464 WIRE 1440 736 1312 736 WIRE 1472 736 1440 736 WIRE 1552 736 1472 736 WIRE -1312 768 -1312 736 WIRE 1312 784 1312 736 WIRE 1472 832 1472 736 WIRE 608 864 608 208 WIRE 752 864 608 864 WIRE 944 864 816 864 WIRE 560 992 560 288 WIRE 752 992 560 992 WIRE 944 992 944 864 WIRE 944 992 816 992 WIRE 1008 992 944 992 WIRE 1152 992 1088 992 WIRE 1312 992 1312 848 WIRE 1312 992 1216 992 WIRE 1472 992 1472 912 WIRE 1472 992 1312 992 FLAG -1312 768 0 FLAG -544 -16 Vct FLAG -640 -112 tank- FLAG -128 -112 tank+ SYMBOL ind2 -688 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -384 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL ind2 -192 -320 M90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 780n SYMATTR Type ind SYMATTR SpiceLine Rser=0.004 Cpar=1pF SYMBOL res -304 -592 R0 SYMATTR InstName R14 SYMATTR Value 2k2 SYMBOL res 192 448 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 22 SYMBOL nmos 272 368 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 352 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV1 SYMBOL res -560 432 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 22 SYMBOL ind2 -960 -336 R0 SYMATTR InstName L6 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 720 224 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 720 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 816 848 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 816 976 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1216 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1296 784 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL res 1440 416 R0 SYMATTR InstName R4 SYMATTR Value 820k SYMBOL res 1472 864 R0 SYMATTR InstName R5 SYMATTR Value 820k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 1µF SYMBOL pnp -240 -256 R180 SYMATTR InstName Q1 SYMBOL pnp 48 -256 M180 SYMATTR InstName Q2 SYMBOL res -304 592 R0 SYMATTR InstName R3 SYMATTR Value 1k5 SYMBOL res 112 608 R0 WINDOW 3 13 26 Left 2 SYMATTR Value 1k5 SYMATTR InstName R9 SYMBOL res -32 -560 R0 SYMATTR InstName R10 SYMATTR Value 11k SYMBOL res 0 480 R0 SYMATTR InstName R11 SYMATTR Value 13k SYMBOL cap 144 -576 R0 SYMATTR InstName C5 SYMATTR Value 10n SYMBOL FerriteBead -944 -144 R180 SYMATTR InstName L3 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL ind2 -544 224 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 5.5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -224 304 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -2 57 VBottom 2 SYMATTR InstName L9 SYMATTR Value 5.5m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL zener -928 448 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D5 SYMATTR Value 1N5371B SYMBOL FerriteBead -944 544 R180 SYMATTR InstName L10 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL res -1168 -688 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R8 SYMATTR Value 22 SYMBOL ind2 992 192 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L7 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=1p SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 44 Left 2 SYMATTR SpiceLine Rser=1 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 992 1008 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L8 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=1p SYMBOL FerriteBead 1104 208 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L11 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" SYMBOL FerriteBead 1184 992 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L12 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" TEXT -1232 792 Left 2 !.tran 0 10m 0m 100n TEXT -1232 856 Left 2 !K1 L1 L2 L3 L4 L5 0.99 TEXT -1312 -752 Left 2 !.model Si3440DV1 VDMOS(Rg=3 Vto=3.6 Rd=150m Rs=112.5m Rb=188m Kp=50 Cgdmax=.2n Cgdmin=.02n Cgs=.2n Cjo=.05n Is=11p ksubthres=.1 mfg=Siliconix Vds=150 Ron=375m Qg=5.4n) TEXT -856 792 Left 2 !.ic I(l6=15m I(L1=15m)) TEXT -848 856 Left 2 !K2 L6 L7 L8 0.99

Even more oops. The extra windings were in the wrong place, and when I put them where I think they ought to go the circuit behaves in a way that it shouldn't.

I found a couple more bugs when I started looking harder, and I don't think I've got rid of all of them yet. Depressing, but design is like that, until you get it right, if you can.

Bill Sloman schrieb am Dienstag, 15. Juni 2021 um 08:40:23 UTC+2:

Hello,

same to me. Didn't get it working in a meaninful manner. ;) Neither did my attempt work as shown in the paper. So I strip it down to the bones now, but still...

On the other hand does the heavily loaded BJT based version for all the lower voltages (without the second L in the output) produce somewhat irregular waveforms, getting closer to rectangle shape but still much less harmonics than a hard switching version. It seems to be clear due to the energy, which the load draws out of the output, so the rectifiers must cut the tops of sine. Something like an in-between of Baxandall and hard-switched Push pull, but still resonating. And load helps to prevent "squegging" - safely in my tries. Thank you for your effort! It's still very interesting! :)

Cheers, Timo

The oops wasn't as bad as I first thought. This is the current version, which isn't all that different from the last one. It seems to work for me, despite a slightly more realistic value (10pF rather than 1pF) for the parallel capacitances of the overwindings (l7 and L8) on the feed-inductor - L6. The overwindings just cancel out the half-sine component of the voltages applied to L11 and L12 leaving something closer to a constant voltage. It still strikes me as a neat idea.

Version 4 SHEET 1 1668 1056 WIRE -1216 -688 -1312 -688 WIRE -1088 -688 -1136 -688 WIRE -944 -688 -1088 -688 WIRE -304 -688 -944 -688 WIRE -32 -688 -304 -688 WIRE 160 -688 -32 -688 WIRE 1488 -688 160 -688 WIRE -304 -624 -304 -688 WIRE -32 -592 -32 -688 WIRE 160 -576 160 -688 WIRE -32 -464 -32 -512 WIRE 160 -464 160 -512 WIRE 160 -464 -32 -464 WIRE -304 -416 -304 -544 WIRE 112 -416 -304 -416 WIRE -304 -352 -304 -416 WIRE 112 -352 112 -416 WIRE -944 -320 -944 -688 WIRE -176 -304 -240 -304 WIRE -32 -304 -32 -464 WIRE -32 -304 -96 -304 WIRE 0 -304 -32 -304 WIRE 48 -304 0 -304 WIRE -944 -208 -944 -240 WIRE -1312 -112 -1312 -688 WIRE -640 -112 -704 -112 WIRE -448 -112 -640 -112 WIRE -128 -112 -384 -112 WIRE 320 -112 -128 -112 WIRE -944 -16 -944 -144 WIRE -544 -16 -944 -16 WIRE -384 -16 -544 -16 WIRE -704 48 -704 -112 WIRE -672 48 -704 48 WIRE -384 48 -384 -16 WIRE -384 48 -592 48 WIRE -240 48 -384 48 WIRE 320 48 320 -112 WIRE 320 48 -160 48 WIRE -1088 144 -1088 -688 WIRE -528 208 -624 208 WIRE 608 208 -448 208 WIRE 720 208 608 208 WIRE 848 208 784 208 WIRE 928 208 848 208 WIRE 1072 208 1008 208 WIRE 1232 208 1136 208 WIRE 1440 208 1232 208 WIRE -624 288 -624 208 WIRE -400 288 -624 288 WIRE -224 288 -400 288 WIRE 560 288 -144 288 WIRE 720 288 560 288 WIRE 848 288 848 208 WIRE 848 288 784 288 WIRE -704 352 -704 48 WIRE 320 368 320 48 WIRE -944 384 -944 -16 WIRE 1440 384 1440 208 WIRE -592 432 -656 432 WIRE -304 432 -304 -256 WIRE -304 432 -512 432 WIRE 0 448 0 -304 WIRE 112 448 112 -256 WIRE 160 448 112 448 WIRE 272 448 240 448 WIRE 1232 480 1232 208 WIRE -944 512 -944 448 WIRE -304 560 -304 432 WIRE 112 576 112 448 WIRE -1312 736 -1312 -32 WIRE -1088 736 -1088 208 WIRE -1088 736 -1312 736 WIRE -944 736 -944 576 WIRE -944 736 -1088 736 WIRE -704 736 -704 448 WIRE -704 736 -944 736 WIRE -400 736 -400 288 WIRE -400 736 -704 736 WIRE -304 736 -304 640 WIRE -304 736 -400 736 WIRE 0 736 0 528 WIRE 0 736 -304 736 WIRE 112 736 112 656 WIRE 112 736 0 736 WIRE 320 736 320 464 WIRE 320 736 112 736 WIRE 1232 736 1232 544 WIRE 1232 736 320 736 WIRE 1312 736 1232 736 WIRE 1440 736 1440 464 WIRE 1440 736 1312 736 WIRE 1472 736 1440 736 WIRE 1552 736 1472 736 WIRE -1312 768 -1312 736 WIRE 1312 784 1312 736 WIRE 1472 832 1472 736 WIRE 608 864 608 208 WIRE 752 864 608 864 WIRE 944 864 816 864 WIRE 560 992 560 288 WIRE 752 992 560 992 WIRE 944 992 944 864 WIRE 944 992 816 992 WIRE 1024 992 944 992 WIRE 1152 992 1104 992 WIRE 1312 992 1312 848 WIRE 1312 992 1216 992 WIRE 1472 992 1472 912 WIRE 1472 992 1312 992 FLAG -1312 768 0 FLAG -544 -16 Vct FLAG -640 -112 tank- FLAG -128 -112 tank+ SYMBOL ind2 -688 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 64 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -384 -128 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL ind2 -192 -320 M90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 780n SYMATTR Type ind SYMATTR SpiceLine Rser=0.004 Cpar=1pF SYMBOL res -304 -592 R0 SYMATTR InstName R14 SYMATTR Value 3k3 SYMBOL res 192 448 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 2.2 SYMBOL nmos 272 368 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 352 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV SYMBOL res -560 432 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 2.2 SYMBOL ind2 -960 -336 R0 SYMATTR InstName L6 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 720 224 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 720 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 816 848 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 816 976 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1216 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1296 784 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL res 1440 416 R0 SYMATTR InstName R4 SYMATTR Value 820k SYMBOL res 1472 864 R0 SYMATTR InstName R5 SYMATTR Value 820k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 1µF SYMBOL pnp -240 -256 R180 SYMATTR InstName Q1 SYMBOL pnp 48 -256 M180 SYMATTR InstName Q2 SYMBOL res -304 592 R0 SYMATTR InstName R3 SYMATTR Value 1k5 SYMBOL res 112 608 R0 WINDOW 3 13 26 Left 2 SYMATTR Value 1k5 SYMATTR InstName R9 SYMBOL res -32 -560 R0 SYMATTR InstName R10 SYMATTR Value 11k SYMBOL res 0 480 R0 SYMATTR InstName R11 SYMATTR Value 13k SYMBOL cap 144 -576 R0 SYMATTR InstName C5 SYMATTR Value 10n SYMBOL ind2 -544 224 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 12.2m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -128 272 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L3 SYMATTR Value 12.2m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL zener -928 448 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D5 SYMATTR Value 1N5371B SYMBOL FerriteBead -944 544 R180 SYMATTR InstName L10 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL res -1168 -688 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R8 SYMATTR Value 22 SYMBOL ind2 1008 1008 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -6 69 VBottom 2 SYMATTR InstName L7 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=10p SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 44 Left 2 SYMATTR SpiceLine Rser=1 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 1024 192 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 48 56 VTop 2 SYMATTR InstName L8 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=10p SYMBOL FerriteBead 1104 208 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L11 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" SYMBOL FerriteBead 1184 992 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L12 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" SYMBOL FerriteBead -944 -176 R180 SYMATTR InstName L9 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p TEXT -1232 792 Left 2 !.tran 0 10m 0m 100n TEXT -1232 856 Left 2 !K1 L1 L2 L3 L4 L5 0.99 TEXT -856 792 Left 2 !.ic I(l6=15m I(L1=15m)) TEXT -848 856 Left 2 !K2 L6 L7 L8 0.99

I hope this is a bit more interesting. I've just up-dated my copy of LT Spice 17, so I hope that components will now stay where I put them.

This is about as simple as the circuit can get. The MOSFets are driven by a centre-tapped 6-turn winding (L5 and L6) and the EFD55-8 former has only got eight pins, which means that on a real circuit you'd have to improvise a bit.

For the circuit to start the bias voltage on the centre tap has to be just high enough for both MOSFets to be turned on, which is a bit too high to let the circuit work properly once it running as intended. The network around D6, D7 and D8 lets bias voltage get pulled down to the point where the circuit will work correctly, once it is operating as intended.

With values chosen, each of D7 and D8 is pulling current out of the bias node for about a quartrer the time, and I imagine that that will probably work over the tolerance range for the MOSFets M1 and M2 - Siliconix Si3.440DV parts which happened to be in the LT Spice component range.

R8 damps the 2.5MHz parastic oscillation driven by the switching transients. A more complex design could have smaller switching transients, but it wouldn't be worth posting here.

L14 is a totally dummy part - it exists to create the waveform V(cancelingV) which is there to make it easier to explain what L8 an L9 were put in to do. If you plot V(n009) + V(cancellingv) or V(n018) - V(cancellingv) you get pretty close to flat +200V and -200V traces, which are a lot easier to filter than the voltage coming out of the rectifiers.

The circuit seems to deliver 4mA at +200V and -200V - 1.6 Watt - and draw 81mA at 24V - 1.95 Watt, which 82% efficiency. Two mA of the current drawn is setting up bias voltages. The inductor resistances aren't properly worked out, so this isn't all that reliable.

I've been swapping e-mails with a couple of expert friends and the idea doesn't seem to be easy to get across.

Version 4 SHEET 1 1944 1284 WIRE -1200 -848 -1312 -848 WIRE -1088 -848 -1136 -848 WIRE -944 -848 -1088 -848 WIRE 0 -848 -944 -848 WIRE 832 -848 0 -848 WIRE 1712 -848 832 -848 WIRE -944 -784 -944 -848 WIRE 0 -704 0 -848 WIRE -944 -672 -944 -704 WIRE 832 -624 832 -848 WIRE -656 -464 -704 -464 WIRE -272 -464 -656 -464 WIRE 96 -464 -208 -464 WIRE 464 -464 176 -464 WIRE 624 -464 464 -464 WIRE -944 -368 -944 -608 WIRE -544 -368 -944 -368 WIRE -384 -368 -544 -368 WIRE -704 -304 -704 -464 WIRE -672 -304 -704 -304 WIRE -384 -304 -384 -368 WIRE -384 -304 -592 -304 WIRE -240 -304 -384 -304 WIRE 624 -304 624 -464 WIRE 624 -304 -160 -304 WIRE 832 -288 832 -544 WIRE 1872 -288 832 -288 WIRE 1872 -224 1872 -288 WIRE 352 -160 -496 -160 WIRE 464 -160 352 -160 WIRE 704 -160 544 -160 WIRE 832 -160 832 -288 WIRE 832 -160 768 -160 WIRE -1312 -112 -1312 -848 WIRE 832 -80 832 -160 WIRE -496 -64 -496 -160 WIRE 352 -64 352 -160 WIRE -1088 144 -1088 -848 WIRE -400 176 -624 176 WIRE 960 176 -320 176 WIRE 1072 176 960 176 WIRE 1200 176 1136 176 WIRE 1280 176 1200 176 WIRE 1424 176 1360 176 WIRE 1584 176 1488 176 WIRE 1792 176 1584 176 WIRE -624 288 -624 176 WIRE -400 288 -624 288 WIRE -288 288 -400 288 WIRE 912 288 -208 288 WIRE 1072 288 912 288 WIRE 1200 288 1200 176 WIRE 1200 288 1136 288 WIRE -944 384 -944 -368 WIRE 1792 384 1792 176 WIRE 624 400 624 -304 WIRE -704 448 -704 -304 WIRE 0 480 0 -624 WIRE 240 480 0 480 WIRE 352 480 352 0 WIRE 352 480 320 480 WIRE 432 480 352 480 WIRE 576 480 512 480 WIRE 1584 480 1584 176 WIRE -944 512 -944 448 WIRE -608 528 -656 528 WIRE -496 528 -496 0 WIRE -496 528 -528 528 WIRE -288 528 -496 528 WIRE -112 528 -208 528 WIRE 0 528 0 480 WIRE 0 528 -112 528 WIRE 0 688 0 528 WIRE 0 688 -240 688 WIRE -240 768 -240 688 WIRE 0 816 0 688 WIRE -1312 976 -1312 -32 WIRE -1088 976 -1088 208 WIRE -1088 976 -1312 976 WIRE -944 976 -944 576 WIRE -944 976 -1088 976 WIRE -704 976 -704 544 WIRE -704 976 -944 976 WIRE -400 976 -400 288 WIRE -400 976 -704 976 WIRE -240 976 -240 832 WIRE -240 976 -400 976 WIRE 0 976 0 896 WIRE 0 976 -240 976 WIRE 624 976 624 496 WIRE 624 976 0 976 WIRE 832 976 832 -16 WIRE 832 976 624 976 WIRE 1264 976 1264 592 WIRE 1264 976 832 976 WIRE 1584 976 1584 544 WIRE 1584 976 1264 976 WIRE 1664 976 1584 976 WIRE 1792 976 1792 464 WIRE 1792 976 1664 976 WIRE 1824 976 1792 976 WIRE 1872 976 1872 -160 WIRE 1872 976 1824 976 WIRE 1920 976 1872 976 WIRE -1312 1008 -1312 976 WIRE 1664 1024 1664 976 WIRE 1824 1072 1824 976 WIRE 960 1104 960 176 WIRE 1104 1104 960 1104 WIRE 1296 1104 1168 1104 WIRE 912 1232 912 288 WIRE 1104 1232 912 1232 WIRE 1296 1232 1296 1104 WIRE 1296 1232 1168 1232 WIRE 1376 1232 1296 1232 WIRE 1504 1232 1456 1232 WIRE 1664 1232 1664 1088 WIRE 1664 1232 1568 1232 WIRE 1824 1232 1824 1152 WIRE 1824 1232 1664 1232 FLAG -1312 1008 0 FLAG -544 -368 Vct FLAG -656 -464 tank- FLAG 1264 512 CancellingV FLAG 464 -464 tank+ FLAG -112 528 Bias SYMBOL ind2 -688 -288 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L1 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.088 Cpar=10p SYMBOL ind2 -256 -288 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L2 SYMATTR Value 0.176m SYMATTR Type ind SYMATTR SpiceLine Rser=0.022 SYMBOL cap -208 -480 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 46 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2.2n SYMBOL res 464 480 M90 WINDOW 0 -26 11 VBottom 2 WINDOW 3 22 8 VTop 2 SYMATTR InstName R1 SYMATTR Value 10 SYMBOL nmos 576 400 R0 SYMATTR InstName M1 SYMATTR Value Si3440DV SYMBOL nmos -656 448 M0 SYMATTR InstName M2 SYMATTR Value Si3440DV SYMBOL res -576 528 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R2 SYMATTR Value 10 SYMBOL ind2 -960 -800 R0 SYMATTR InstName L7 SYMATTR Value 2.2m SYMATTR SpiceLine Ipk=5A Rser=0.8 Rpar=100k Cpar=10p SYMBOL diode 1072 192 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D1 SYMATTR Value RFU02VS8S SYMBOL diode 1072 304 R270 WINDOW 0 32 32 VTop 2 WINDOW 3 0 32 VBottom 2 SYMATTR InstName D2 SYMATTR Value RFU02VS8S SYMBOL diode 1168 1088 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D3 SYMATTR Value RFU02VS8S SYMBOL diode 1168 1216 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName D4 SYMATTR Value RFU02VS8S SYMBOL cap 1568 480 R0 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL cap 1648 1024 R0 WINDOW 3 17 75 Left 2 SYMATTR Value 10n SYMATTR InstName C3 SYMBOL res 1792 416 R0 SYMATTR InstName R4 SYMATTR Value 47k SYMBOL res 1824 1104 R0 SYMATTR InstName R5 SYMATTR Value 47k SYMBOL cap -1104 144 R0 SYMATTR InstName C4 SYMATTR Value 1µ SYMBOL res 0 848 R0 WINDOW 3 21 18 Left 2 SYMATTR Value 4k3 SYMATTR InstName R11 SYMBOL ind2 -416 192 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 4 56 VBottom 2 SYMATTR InstName L4 SYMATTR Value 12.2m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL ind2 -192 272 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L3 SYMATTR Value 12.2m SYMATTR Type ind SYMATTR SpiceLine Rser=10 Cpar=10p SYMBOL zener -928 448 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D5 SYMATTR Value 1N5371B SYMBOL FerriteBead -944 544 R180 SYMATTR InstName L15 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL ind2 1360 1248 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 -6 69 VBottom 2 SYMATTR InstName L9 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=10p SYMBOL voltage -1312 -128 R0 WINDOW 123 0 0 Left 0 WINDOW 39 24 44 Left 2 SYMATTR SpiceLine Rser=1 SYMATTR InstName V1 SYMATTR Value 24 SYMBOL ind2 1376 160 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 48 56 VTop 2 SYMATTR InstName L8 SYMATTR Value 153m SYMATTR SpiceLine Rser=1 Cpar=10p SYMBOL FerriteBead 1456 176 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L11 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f SYMBOL FerriteBead 1536 1232 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L12 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f mfg="Würth Elektronik" pn="74275010 WE-UKW 6050" SYMBOL FerriteBead -944 -640 R180 SYMATTR InstName L16 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0118 Rpar=870 Cpar=1.1p SYMBOL FerriteBead -1168 -848 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L13 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f SYMBOL ind2 1248 496 R0 SYMATTR InstName L14 SYMATTR Value 153m SYMBOL ind2 -192 512 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L5 SYMATTR Value 7.02µ SYMBOL ind2 336 464 R90 WINDOW 0 4 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName L6 SYMATTR Value 7.02µ SYMBOL res 0 -672 R0 WINDOW 3 21 18 Left 2 SYMATTR Value 18k SYMATTR InstName R3 SYMBOL cap -256 768 R0 SYMATTR InstName C5 SYMATTR Value 100n SYMBOL res 832 -592 R0 WINDOW 3 21 18 Left 2 SYMATTR Value 15k SYMATTR InstName R6 SYMBOL diode -480 0 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D7 SYMATTR Value 1N4148 SYMBOL diode 368 0 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D8 SYMATTR Value 1N4148 SYMBOL res 512 -160 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R7 SYMATTR Value 820 SYMBOL cap 1856 -224 R0 SYMATTR InstName C6 SYMATTR Value 100n SYMBOL zener 848 -16 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D6 SYMATTR Value BZX84C10L SYMBOL res 128 -464 M90 WINDOW 0 -18 21 VBottom 2 WINDOW 3 19 15 VTop 2 SYMATTR InstName R8 SYMATTR Value 33 SYMBOL FerriteBead 736 -160 R90 WINDOW 0 -16 0 VBottom 2 SYMATTR InstName L10 SYMATTR Value 12µ SYMATTR SpiceLine Ipk=3 Rser=0.0083 Rpar=880 Cpar=715f TEXT -1232 1032 Left 2 !.tran 0 10m 0m 10n TEXT -1232 1096 Left 2 !K1 L1 L2 L3 L4 L5 L6 0.99 TEXT -856 1032 Left 2 !.ic I(L7=1u) I(L1=1u) V(Bias)=3.824 TEXT -848 1096 Left 2 !K2 L7 L8 L9 L14 0.99