another goofy boost converter architecture

Sort of a hybrid of a flyback and a sepic. I call it a skeptic converter.

I don't trust the efficiency calculation, especially when it goes over 100%.

Version 4 SHEET 1 1920 1092 WIRE 224 96 96 96 WIRE -48 144 -96 144 WIRE -16 144 -48 144 WIRE 96 144 96 96 WIRE 240 144 96 144 WIRE 320 144 240 144 WIRE 464 144 400 144 WIRE 528 144 464 144 WIRE 656 144 608 144 WIRE 912 144 864 144 WIRE 1056 144 992 144 WIRE 1152 144 1056 144 WIRE 1264 144 1216 144 WIRE 1312 144 1264 144 WIRE 1440 144 1392 144 WIRE 1456 144 1440 144 WIRE 1472 144 1456 144 WIRE -96 176 -96 144 WIRE 96 176 96 144 WIRE 240 240 240 144 WIRE 320 240 240 240 WIRE 464 240 464 144 WIRE 464 240 384 240 WIRE 1264 240 1264 144 WIRE 1312 240 1264 240 WIRE 1440 240 1440 144 WIRE 1440 240 1376 240 WIRE 1440 288 1440 240 WIRE 608 304 576 304 WIRE 656 304 656 144 WIRE 656 304 608 304 WIRE 736 304 656 304 WIRE 864 304 864 144 WIRE 864 304 800 304 WIRE -96 320 -96 256 WIRE 96 320 96 256 WIRE 656 336 656 304 WIRE 1056 336 1056 144 WIRE 864 352 864 304 WIRE 304 384 272 384 WIRE 400 384 368 384 WIRE 1440 400 1440 352 WIRE 656 432 656 416 WIRE -48 448 -96 448 WIRE -16 448 -48 448 WIRE 144 448 96 448 WIRE 272 448 272 384 WIRE 272 448 224 448 WIRE 304 448 272 448 WIRE 400 448 400 384 WIRE 400 448 368 448 WIRE 864 448 864 416 WIRE -96 480 -96 448 WIRE 1056 480 1056 416 WIRE 272 512 272 448 WIRE 304 512 272 512 WIRE 400 512 400 448 WIRE 400 512 368 512 WIRE 432 512 400 512 WIRE 560 512 512 512 WIRE 608 512 560 512 WIRE 96 576 96 448 WIRE 160 576 96 576 WIRE 272 576 272 512 WIRE 272 576 224 576 WIRE 304 576 272 576 WIRE 400 576 400 512 WIRE 400 576 368 576 WIRE 1056 592 1056 544 WIRE -96 624 -96 560 WIRE 400 624 368 624 WIRE 544 624 512 624 WIRE 656 624 656 528 WIRE 656 624 624 624 WIRE 368 656 368 624 WIRE 1120 672 1056 672 WIRE 1264 672 1200 672 WIRE 1312 672 1264 672 WIRE 1328 672 1312 672 WIRE 512 688 512 624 WIRE 512 688 400 688 WIRE 656 688 656 624 WIRE 96 704 96 576 WIRE 144 704 96 704 WIRE 320 704 144 704 WIRE 448 720 400 720 WIRE 464 720 448 720 WIRE 512 720 512 688 WIRE 1056 720 1056 672 WIRE 1264 736 1264 672 WIRE 368 768 368 752 WIRE 384 768 384 752 WIRE 384 768 368 768 WIRE 368 784 368 768 WIRE 512 816 512 784 WIRE 656 816 656 768 WIRE 400 832 368 832 WIRE 368 864 368 832 WIRE 1056 880 1056 800 WIRE 1264 880 1264 800 WIRE 656 896 400 896 WIRE 736 896 656 896 WIRE 864 896 816 896 WIRE 896 896 864 896 WIRE 96 912 96 704 WIRE 320 912 96 912 WIRE 96 928 96 912 WIRE 448 928 400 928 WIRE 480 928 448 928 WIRE 656 928 656 896 WIRE 368 976 368 960 WIRE 384 976 384 960 WIRE 384 976 368 976 WIRE 368 992 368 976 WIRE 96 1040 96 992 WIRE 656 1040 656 1008 FLAG 1456 144 VP FLAG 656 816 0 FLAG 96 320 0 FLAG 608 304 DRAIN FLAG 560 512 GATE FLAG 864 448 0 FLAG 1056 592 0 FLAG 1056 880 0 FLAG 1312 672 EFF FLAG 1264 880 0 FLAG 96 1040 0 FLAG 144 704 rc FLAG 1440 400 0 FLAG 224 96 9V FLAG 368 784 0 FLAG 400 624 9V FLAG 448 720 0.2V FLAG -96 320 0 FLAG -48 144 0.2V FLAG 368 992 0 FLAG 400 832 9V FLAG -96 624 0 FLAG -48 448 1.25V FLAG 448 928 1.25V FLAG 656 1040 0 FLAG 864 896 VP FLAG 512 816 0 SYMBOL ind2 512 160 R270 WINDOW 0 -41 56 VTop 2 WINDOW 3 -53 53 VBottom 2 SYMATTR InstName L1 SYMATTR Value 5µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.06 SYMBOL schottky 1152 160 R270 WINDOW 0 -41 30 VTop 2 WINDOW 3 -49 27 VBottom 2 SYMATTR InstName D1 SYMATTR Value 10MQ060N SYMATTR Description Diode SYMATTR Type diode SYMBOL voltage 96 160 R0 WINDOW 0 60 48 Left 2 WINDOW 3 67 80 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 9 SYMBOL nmos 608 432 R0 WINDOW 0 -55 -55 Left 2 WINDOW 3 -101 -22 Left 2 SYMATTR InstName M1 SYMATTR Value Si7218DN SYMBOL ind2 896 160 R270 WINDOW 0 -32 56 VTop 2 WINDOW 3 -41 57 VBottom 2 SYMATTR InstName L2 SYMATTR Value 5µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.06 SYMBOL res 528 496 R90 WINDOW 0 -15 56 VBottom 2 WINDOW 3 46 56 VTop 2 SYMATTR InstName R3 SYMATTR Value 10 SYMBOL res 1296 160 R270 WINDOW 0 -38 31 VTop 2 WINDOW 3 -11 86 VBottom 2 SYMATTR InstName R6 SYMATTR Value 1m SYMBOL cap 1376 224 R90 WINDOW 0 68 59 VBottom 2 WINDOW 3 42 -8 VTop 2 SYMATTR InstName C3 SYMATTR Value 50m SYMBOL res 304 160 R270 WINDOW 0 -37 24 VTop 2 WINDOW 3 -11 88 VBottom 2 SYMATTR InstName R8 SYMATTR Value 1m SYMBOL cap 384 224 R90 WINDOW 0 71 54 VBottom 2 WINDOW 3 43 0 VTop 2 SYMATTR InstName C6 SYMATTR Value 50m SYMBOL res 1040 320 R0 WINDOW 0 59 38 Left 2 WINDOW 3 58 74 Left 2 SYMATTR InstName R9 SYMATTR Value 500 SYMBOL cap 1040 480 R0 WINDOW 0 -46 35 Left 2 WINDOW 3 -50 68 Left 2 SYMATTR InstName C7 SYMATTR Value 30p SYMBOL bv 1056 704 R0 WINDOW 3 -110 247 Left 2 WINDOW 0 -83 97 Left 2 SYMATTR Value V= LIMIT (0, 100 * I(R6) * V(VP) / ( I(R8) * 9 ), 120) SYMATTR InstName B1 SYMBOL res 1216 656 R90 WINDOW 0 70 60 VBottom 2 WINDOW 3 78 61 VTop 2 SYMATTR InstName R1 SYMATTR Value 1K SYMBOL cap 1248 736 R0 WINDOW 0 -37 63 Left 2 WINDOW 3 -43 94 Left 2 SYMATTR InstName C2 SYMATTR Value 10n SYMBOL Digital\\schmtinv 160 512 R0 SYMATTR InstName A1 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=0.5 SYMATTR SpiceLine Td=5n SYMBOL cap 80 928 R0 WINDOW 0 44 60 Left 2 WINDOW 3 37 92 Left 2 SYMATTR InstName C4 SYMATTR Value 500p SYMBOL res 128 464 R270 WINDOW 0 88 58 VTop 2 WINDOW 3 74 57 VBottom 2 SYMATTR InstName R4 SYMATTR Value 2K SYMBOL Digital\\schmtinv 304 448 R0 SYMATTR InstName A2 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 384 R0 SYMATTR InstName A3 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 512 R0 SYMATTR InstName A4 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 320 R0 SYMATTR InstName A5 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL cap 1424 288 R0 WINDOW 0 -70 43 Left 2 WINDOW 3 -64 77 Left 2 SYMATTR InstName C5 SYMATTR Value 4µ SYMBOL res 640 320 R0 WINDOW 0 47 70 Left 2 WINDOW 3 41 102 Left 2 SYMATTR InstName R7 SYMATTR Value 1m SYMBOL res 640 672 R0 WINDOW 0 70 52 Left 2 WINDOW 3 75 86 Left 2 SYMATTR InstName R10 SYMATTR Value 0.2 SYMBOL Comparators\\LT1011 368 704 M0 SYMATTR InstName U1 SYMBOL voltage -96 160 R0 WINDOW 0 63 53 Left 2 WINDOW 3 61 85 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V1 SYMATTR Value 0.2 SYMBOL Comparators\\LT1011 368 912 M0 SYMATTR InstName U2 SYMBOL voltage -96 464 R0 WINDOW 0 61 45 Left 2 WINDOW 3 54 83 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V3 SYMATTR Value 1.25 SYMBOL res 640 912 R0 WINDOW 0 -56 37 Left 2 WINDOW 3 -57 71 Left 2 SYMATTR InstName R5 SYMATTR Value 1K SYMBOL res 832 880 R90 WINDOW 0 69 56 VBottom 2 WINDOW 3 74 56 VTop 2 SYMATTR InstName R11 SYMATTR Value 37.4K SYMBOL cap 800 288 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2µ SYMBOL res 640 608 R90 WINDOW 0 65 54 VBottom 2 WINDOW 3 71 54 VTop 2 SYMATTR InstName R2 SYMATTR Value 1K SYMBOL cap 496 720 R0 WINDOW 0 54 32 Left 2 WINDOW 3 43 63 Left 2 SYMATTR InstName C8 SYMATTR Value 300p SYMBOL schottky 880 416 R180 WINDOW 0 42 2 Left 2 WINDOW 3 -44 -85 Left 2 SYMATTR InstName D2 SYMATTR Value 10MQ060N SYMATTR Description Diode SYMATTR Type diode TEXT 1184 576 Left 2 !.tran 0 4m 0 10n uic TEXT 1168 480 Left 2 ;SKEPTIC CONVERTER TEXT 1208 528 Left 2 ;JL July 3 2013 TEXT 688 128 Left 2 !K L1 L2 0.99 TEXT 192 624 Left 2 ;74HC14 TEXT 160 504 Left 2 ;OSC TEXT 736 176 Left 2 ;1:1 TEXT 160 808 Left 2 ;USE LM393

--
John Larkin                  Highland Technology Inc 
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    
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Reply to
John Larkin
Loading thread data ...

Interesting equation for efficiency ?>:-} ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

Patent it, quickly! :-)

The reason for that are the very large caps C3 and C6 which are not in your efficiency calc. If you take those out or set them to 50pF or something, it's all in the green. Peaks at 92% on the ramp-up but then efficiency really goes to pots as the output voltage comes up.

[SPICE file]
--
Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

That sure is a strange looking expression for efficiency. Where did that come from? Wouldn't efficiency be a long average of output power divided by a long average of input power. ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

Yeah, technically you have to integrate. But with switchers it does not require long averages if one does not use large caps in there. I found that my simple non-integrated values jibe quite well with the circuit later once it comes from the assemblers.

--
Regards, Joerg 

http://www.analogconsultants.com/
Reply to
Joerg

Good name. It makes me sceptical about your design abilities.

Of course. The schematic is totally flawed.

Vladimir Vassilevsky DSP and Mixed Signal Designs

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Reply to
Vladimir Vassilevsky

Still a weird equation. Who dreamt (or nightmared) that?

In PSpice Probe (post-processor) one uses the "avgx" function and average over a cycle (if you like). ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

Vladimir! You're questioning the abilities of the master! That will get you thoroughly denigrated >:-} ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

May I suggest septic converter? Looks like even better name for the circuit.

Vladimir Vassilevsky DSP and Mixed Signal Designs

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Reply to
Vladimir Vassilevsky

They are inside my calculation. The over-100 thing probably results from energy stored in the inductors during startup. That goes away with a bigger load cap. I'm using a small cap now to speed up testing.

C3 and C6 smooth out the input/output currents to make the averages observable.

It's the 90% that I don't trust. I guess I should add in some inductor losses. I'm getting gate drive for free, too.

Reply to
John Larkin

Power_out / Power_in sounds like "efficiency" to me.

Reply to
John Larkin

I don't suppose you'd care to say anything specific. You know, facts.

Are you claiming that it isn't charging the output cap?

Reply to
John Larkin

Initially C1 is charged to 9V. When M1 turns on, then virtually infinite discharge current of C1 flows through it. In addition to that, some current ramps up in L1. When M1 turns off, the L1 current has nowhere to go, so the drain voltage jumps to virtually infinite voltage.

So?

VLV

Reply to
Vladimir Vassilevsky

No, initially it's charged to zero. It does charge through L1+L2+C5 to about 9 volts.

When M1 turns on, then virtually infinite

It's limited by the drain current capacity of the fet. It's about 8 amps peak in this sim, but I'll probably use a smaller fet in real life. The energy in C1 is small, so no harm is done.

One virtue of this circuit over a simple boost is that the startup current doesn't blast through into the large (eventually 4000 uF) load cap. My customer wouldn't like that. And at this high boost ratio, it's more efficient than a sepic... which has its own surge mechanism.

In addition to that, some

Any flyback sort of architecture has a leakage inductance spike. These bifalar 1:1 dual inductors have K over 0.99, which helps a lot. The sim shows the drain spiking to about +39 shortly after startup, rather short of infinity. The energy in the leakage inductance gets dumped into the drain capacitance. So if I add a snubber at the drain, it will be for EMI.

It seems to work fine. The parts are super cheap, and it takes less parts than buying a typical switchmode controller chip.

The capacitor top-off behavior is elegant.

Reply to
John Larkin

But I*V is _instantaneous_ power, not average over a cycle, or over some longer period. ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
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Reply to
Jim Thompson

A slight rearrangement produces the tapped-inductor boost doubler, henceforth the Trouble Converter.

It has a better boost ratio than the Skeptic, and is a little more efficient.

Version 4 SHEET 1 1920 1092 WIRE 160 96 96 96 WIRE 224 96 160 96 WIRE -48 144 -96 144 WIRE -16 144 -48 144 WIRE 160 144 160 96 WIRE 208 144 160 144 WIRE 320 144 288 144 WIRE 464 144 400 144 WIRE 528 144 464 144 WIRE 656 144 608 144 WIRE 704 144 656 144 WIRE 832 144 784 144 WIRE 960 144 896 144 WIRE 1056 144 960 144 WIRE 1104 144 1056 144 WIRE 1216 144 1168 144 WIRE 1248 144 1216 144 WIRE 1360 144 1328 144 WIRE 1488 144 1440 144 WIRE 1504 144 1488 144 WIRE 1520 144 1504 144 WIRE -96 176 -96 144 WIRE 96 176 96 96 WIRE 960 208 960 144 WIRE 160 240 160 144 WIRE 320 240 160 240 WIRE 464 240 464 144 WIRE 464 240 384 240 WIRE 1216 240 1216 144 WIRE 1312 240 1216 240 WIRE 1488 240 1488 144 WIRE 1488 240 1376 240 WIRE 1488 288 1488 240 WIRE 608 304 576 304 WIRE 656 304 656 144 WIRE 656 304 608 304 WIRE 960 304 960 272 WIRE -96 320 -96 256 WIRE 96 320 96 256 WIRE 656 336 656 304 WIRE 1056 336 1056 144 WIRE 304 384 272 384 WIRE 400 384 368 384 WIRE 1488 400 1488 352 WIRE 656 432 656 416 WIRE -48 448 -96 448 WIRE -16 448 -48 448 WIRE 144 448 96 448 WIRE 272 448 272 384 WIRE 272 448 224 448 WIRE 304 448 272 448 WIRE 400 448 400 384 WIRE 400 448 368 448 WIRE -96 480 -96 448 WIRE 1056 480 1056 416 WIRE 272 512 272 448 WIRE 304 512 272 512 WIRE 400 512 400 448 WIRE 400 512 368 512 WIRE 432 512 400 512 WIRE 560 512 512 512 WIRE 608 512 560 512 WIRE 96 576 96 448 WIRE 160 576 96 576 WIRE 272 576 272 512 WIRE 272 576 224 576 WIRE 304 576 272 576 WIRE 400 576 400 512 WIRE 400 576 368 576 WIRE 1056 592 1056 544 WIRE -96 624 -96 560 WIRE 400 624 368 624 WIRE 544 624 512 624 WIRE 656 624 656 528 WIRE 656 624 624 624 WIRE 368 656 368 624 WIRE 1120 672 1056 672 WIRE 1264 672 1200 672 WIRE 1408 672 1344 672 WIRE 1456 672 1408 672 WIRE 1472 672 1456 672 WIRE 512 688 512 624 WIRE 512 688 400 688 WIRE 656 688 656 624 WIRE 96 704 96 576 WIRE 96 704 -16 704 WIRE 144 704 96 704 WIRE 320 704 144 704 WIRE 448 720 400 720 WIRE 464 720 448 720 WIRE 512 720 512 688 WIRE 1056 720 1056 672 WIRE 1408 736 1408 672 WIRE -16 752 -16 704 WIRE 368 768 368 752 WIRE 384 768 384 752 WIRE 384 768 368 768 WIRE 368 784 368 768 WIRE 512 816 512 784 WIRE 656 816 656 768 WIRE 400 832 368 832 WIRE 368 864 368 832 WIRE -16 880 -16 816 WIRE 1056 880 1056 800 WIRE 1408 880 1408 800 WIRE 656 896 400 896 WIRE 736 896 656 896 WIRE 864 896 816 896 WIRE 896 896 864 896 WIRE 96 912 96 704 WIRE 320 912 96 912 WIRE 448 928 400 928 WIRE 480 928 448 928 WIRE 656 928 656 896 WIRE 368 976 368 960 WIRE 384 976 384 960 WIRE 384 976 368 976 WIRE 368 992 368 976 WIRE 656 1040 656 1008 FLAG 1504 144 VP FLAG 656 816 0 FLAG 96 320 0 FLAG 608 304 DRAIN FLAG 560 512 GATE FLAG 960 304 0 FLAG 1056 592 0 FLAG 1056 880 0 FLAG 1456 672 EFF FLAG 1408 880 0 FLAG -16 880 0 FLAG 144 704 rc FLAG 1488 400 0 FLAG 224 96 9V FLAG 368 784 0 FLAG 400 624 9V FLAG 448 720 0.2V FLAG -96 320 0 FLAG -48 144 0.2V FLAG 368 992 0 FLAG 400 832 9V FLAG -96 624 0 FLAG -48 448 1.25V FLAG 448 928 1.25V FLAG 656 1040 0 FLAG 864 896 VP FLAG 512 816 0 SYMBOL ind2 512 160 R270 WINDOW 0 -41 56 VTop 2 WINDOW 3 -47 54 VBottom 2 SYMATTR InstName L1 SYMATTR Value 5µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.06 SYMBOL schottky 1104 160 R270 WINDOW 0 -41 30 VTop 2 WINDOW 3 -49 27 VBottom 2 SYMATTR InstName D1 SYMATTR Value 10MQ060N SYMATTR Description Diode SYMATTR Type diode SYMBOL voltage 96 160 R0 WINDOW 0 -55 102 Left 2 WINDOW 3 -47 131 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 9 SYMBOL nmos 608 432 R0 WINDOW 0 93 53 Left 2 WINDOW 3 91 98 Left 2 SYMATTR InstName M1 SYMATTR Value Si7218DN SYMBOL ind2 688 160 R270 WINDOW 0 -32 56 VTop 2 WINDOW 3 -41 57 VBottom 2 SYMATTR InstName L2 SYMATTR Value 5µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.06 SYMBOL res 528 496 R90 WINDOW 0 -15 56 VBottom 2 WINDOW 3 46 56 VTop 2 SYMATTR InstName R3 SYMATTR Value 10 SYMBOL res 1344 160 R270 WINDOW 0 -38 31 VTop 2 WINDOW 3 -11 86 VBottom 2 SYMATTR InstName R6 SYMATTR Value 1m SYMBOL cap 1312 256 R270 WINDOW 0 -47 8 VTop 2 WINDOW 3 -20 66 VBottom 2 SYMATTR InstName C3 SYMATTR Value 25m SYMBOL res 304 160 R270 WINDOW 0 -37 30 VTop 2 WINDOW 3 -10 80 VBottom 2 SYMATTR InstName R8 SYMATTR Value 1m SYMBOL cap 320 256 R270 WINDOW 0 -44 7 VTop 2 WINDOW 3 -17 66 VBottom 2 SYMATTR InstName C6 SYMATTR Value 25m SYMBOL res 1040 320 R0 WINDOW 0 59 38 Left 2 WINDOW 3 58 74 Left 2 SYMATTR InstName R9 SYMATTR Value 500 SYMBOL cap 1040 480 R0 WINDOW 0 -46 35 Left 2 WINDOW 3 -50 68 Left 2 SYMATTR InstName C7 SYMATTR Value 30p SYMBOL bv 1056 704 R0 WINDOW 3 -110 247 Left 2 WINDOW 0 -83 97 Left 2 SYMATTR Value V= LIMIT (0, 100 * I(R6) * V(VP) / ( I(R8) * 9 ), 120) SYMATTR InstName B1 SYMBOL res 1216 656 R90 WINDOW 0 70 60 VBottom 2 WINDOW 3 78 61 VTop 2 SYMATTR InstName R1 SYMATTR Value 1K SYMBOL cap 1392 736 R0 WINDOW 0 -37 63 Left 2 WINDOW 3 -43 94 Left 2 SYMATTR InstName C2 SYMATTR Value 8n SYMBOL Digital\\schmtinv 160 512 R0 SYMATTR InstName A1 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=0.5 SYMATTR SpiceLine Td=5n SYMBOL cap -32 752 R0 WINDOW 0 44 60 Left 2 WINDOW 3 37 92 Left 2 SYMATTR InstName C4 SYMATTR Value 500p SYMBOL res 128 464 R270 WINDOW 0 88 58 VTop 2 WINDOW 3 74 57 VBottom 2 SYMATTR InstName R4 SYMATTR Value 2K SYMBOL Digital\\schmtinv 304 448 R0 SYMATTR InstName A2 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 384 R0 SYMATTR InstName A3 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 512 R0 SYMATTR InstName A4 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL Digital\\schmtinv 304 320 R0 SYMATTR InstName A5 SYMATTR Value2 Vhigh=5 Vt=2.5 Vh=1 SYMATTR SpiceLine Td=5n SYMBOL cap 1472 288 R0 WINDOW 0 -70 43 Left 2 WINDOW 3 -64 77 Left 2 SYMATTR InstName C5 SYMATTR Value 5µ SYMBOL res 640 320 R0 WINDOW 0 47 70 Left 2 WINDOW 3 41 102 Left 2 SYMATTR InstName R7 SYMATTR Value 1m SYMBOL res 640 672 R0 WINDOW 0 70 52 Left 2 WINDOW 3 75 86 Left 2 SYMATTR InstName R10 SYMATTR Value 0.2 SYMBOL Comparators\\LT1011 368 704 M0 SYMATTR InstName U1 SYMBOL voltage -96 160 R0 WINDOW 0 30 101 Left 2 WINDOW 3 26 131 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V1 SYMATTR Value 0.2 SYMBOL Comparators\\LT1011 368 912 M0 SYMATTR InstName U2 SYMBOL voltage -96 464 R0 WINDOW 0 32 98 Left 2 WINDOW 3 26 131 Left 2 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V3 SYMATTR Value 1.25 SYMBOL res 640 912 R0 WINDOW 0 -56 37 Left 2 WINDOW 3 -57 71 Left 2 SYMATTR InstName R5 SYMATTR Value 1K SYMBOL res 832 880 R90 WINDOW 0 69 56 VBottom 2 WINDOW 3 74 56 VTop 2 SYMATTR InstName R11 SYMATTR Value 37.4K SYMBOL cap 896 128 R90 WINDOW 0 68 32 VBottom 2 WINDOW 3 73 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 2µ SYMBOL res 640 608 R90 WINDOW 0 65 54 VBottom 2 WINDOW 3 71 54 VTop 2 SYMATTR InstName R2 SYMATTR Value 1K SYMBOL cap 496 720 R0 WINDOW 0 54 32 Left 2 WINDOW 3 43 63 Left 2 SYMATTR InstName C8 SYMATTR Value 300p SYMBOL schottky 976 272 R180 WINDOW 0 76 -8 Left 2 WINDOW 3 50 -48 Left 2 SYMATTR InstName D2 SYMATTR Value 10MQ060N SYMATTR Description Diode SYMATTR Type diode SYMBOL ind 192 160 R270 WINDOW 0 -35 35 VTop 2 WINDOW 3 -8 78 VBottom 2 SYMATTR InstName L3 SYMATTR Value 25n SYMBOL ind 1248 688 R270 WINDOW 0 -31 55 VTop 2 WINDOW 3 -41 57 VBottom 2 SYMATTR InstName L4 SYMATTR Value 3m SYMBOL ind 1232 160 R270 WINDOW 0 -36 38 VTop 2 WINDOW 3 -9 85 VBottom 2 SYMATTR InstName L5 SYMATTR Value 25n TEXT 1184 576 Left 2 !.tran 0 25m 0 5n uic TEXT 1168 480 Left 2 ;TROUBLE CONVERTER TEXT 1208 528 Left 2 ;JL July 4 2013 TEXT 584 88 Left 2 !K L1 L2 0.99 TEXT 192 624 Left 2 ;74HC14 TEXT 160 504 Left 2 ;OSC TEXT 160 808 Left 2 ;USE LM393 TEXT 1200 792 Left 2 ;25 KHz

Reply to
John Larkin

Makes no sense. I average it over the period of interest.

My numerator and denominator are what the 9 volt supply has to furnish and what the load (a cap, in this case) absorbs. I want to see efficiency as a function of time, during charging, because that's what I want to see.

The filters on the input and output current make them plot nicely. Real-life power supplies do, after all, have input and output bypass caps. My customer's battery won't see the mosfet instantaneous current; he cares about the current he can measure, and the total energy he has to furnish, which is the data I'm generating.

I could add a bypass cap across the 9V source if that would make you happy.

Reply to
John Larkin

Another flawed design. Again, C1 does hard discharge in L1 L2 M1. Why can't you just make classic transformer flyback?

VLV

Reply to
Vladimir Vassilevsky

A design isn't flawed if it works fine. Discharging C1 does no harm. L1 and L2 will have copper resistance and the fet wouldn't care if they didn't.

The customer is going to have to charge a lot more than 2 uF at startup: I have a moral right to some input bypass caps.

That's an application issue. In the space I have, with the specs I have, this looks good. I'd need custom magnatics to do a flyback, and that doesn't make sense now.

Why are you hostile to new ideas? Is anything other than a "classic flyback" unsanctioned? Threatening? Do you ever brainstorm? Do you slap everything down as soon as it's suggested?

Reply to
John Larkin

I am hostile to flawed designs. Especially if advertized as new and great.

Aren't somebody like you supposed to grew up from diapers design league?

I solve problems. And I do it very well.

Vladimir Vassilevsky DSP and Mixed Signal Designs

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Reply to
Vladimir Vassilevsky

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