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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
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approximately
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current,
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making
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into
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are
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Yeah, but every time I looked at a digital solution I found that things
fall apart when you need cycle-to-cycle performance at much more than
100kHz. Same for the loops, many of mine have to operate at 50kHz BW or
higher and there's often two or three loops operating simultaneously.
Even a serious uC runs out of coal real fast then.


Quoted text here. Click to load it

Many do these days. Same with OVP schemes that occasionally backfire.
Sometimes I goose them in a way that they think everything is in the
green. For example, by putting the FB node on an artificial pedestal.
Then it never goes into foldback. If you don't have a precision
reference available for that you can concoct a simple circuit that
sources current into the FB pin when the FB voltage wants to drop
towards the threshold where foldback would kick in. If an opamp from a
quad-pack happens to be vacant that makes things easy. But even a stiff
voltage source and a diode is sometimes enough to fool the chip into
permanent non-foldback. One the FB voltage is above a limit where the
diode quits conducting things look like normal.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements

Quoted text here. Click to load it
approximately
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current,
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making
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into
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are
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up
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driver,
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Sure, but it seems silly to add an opamp active diode to fool a chip that's
already too complex.

TI has a DSP-core digital power controller with picosecond PWM resolution. I'll
ask Rob what the part number is.

You could also give a cheap uP a little help around the edges, like a gate
driver that shuts off when peak current is sensed, something like that. One
advantage of designing everything yourself is that you can understand it; lots
of complex analog chips are mysterious about what they actually do. Like an
opamp on the block diagram with three inputs... what's that supposed to do?


--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
Quoted text here. Click to load it
approximately
Quoted text here. Click to load it
current,
Quoted text here. Click to load it
making
Quoted text here. Click to load it
into
Quoted text here. Click to load it
are
Quoted text here. Click to load it
up
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driver,
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start
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Nah, foldback makes a lot of sense in many situations. For example, I
just designed a unit that also has to supply a couple amps to
miscellaneous external 12V gear. Small displays and such, and if the
regulator were capable of dumping 2A into a shorted out electrolytic,
changes are there would be a serious *KAPHOOF* situation. If I wanted no
foldback for some reason all I need to do that is place three parts. Two
resistors and one diode. About 50 millibucks worth.


Quoted text here. Click to load it
I'll
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That is nice. As long at it has the horsewpower for a reasonably fast
loop (as in tens of kHz) and won't require the San Onofre power plant to
be fired up again in order to operate.


Quoted text here. Click to load it


See? There the digital situation already requires extra hardware,
including extra ICs. There is no way to properly drive a big fat
switcher from a 5V logic device of any kind. Because you need +10V (or
better 12-15V) to turn the power FETs on and -5V or so to turn the off
with gusto. Else the efficiency will suffer. All this logic-level
driving is no good when efficiency is paramount.

Pretty soon you'll find out that leading-edge blanking just isn't in the
cards with a uC, its internal comparator has the acceleration of an
Isetta, some high priority interrupt keeps trampling on the loop
performance, and it can't prevent a loud bang when the regulator goes
into CCM and the inductor core saturates within a microsecond or so.


Quoted text here. Click to load it

That almost drove people nuts when we had transistors on the schematic
of an IC design that had numerous collectors.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements

Good grief, why use complicated LTC chips and microprocessors and stuff?

Scope the fet drain; it's really cool.


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TEXT 1032 488 Left 2 !.tran 0 5m 0 10n uic
TEXT 1064 392 Left 2 ;DUMB BOOST
TEXT 1048 440 Left 2 ;JL  June 28 2013
TEXT 648 104 Left 2 !K L1 L2 0.95
TEXT 144 624 Left 2 ;74HC14



--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
Quoted text here. Click to load it

That's how I designed the boost converter on my first mass-produced
design in the early 90's, less the transformer (used only an inductor).
But I used a BJT instead of the 7002 because that saved another penny.
No kidding, and we also had the inductor made in Asia because then it
cost less than a catalog part from a distributor.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements
On Fri, 28 Jun 2013 21:33:22 -0700, John Larkin wrote:

<LTSpice listing>

I like your use of a B source, to plot efficiency. Must remember that one.

I rehashed it a bit, to include "proper" 74HC14s (actually a 74HC .lib
file that purports to come from LT, but I can't remember where I got it
from), and a real-life Zetex 39V zener.

Little if any difference.

--  
"For a successful technology, reality must take precedence  
over public relations, for nature cannot be fooled."
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Re: Boost Converter Efficiency Improvements
Fred Abse wrote:
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I'd use a CD40106 instead. Even such logic-level FETs aren't all that
happy at 5V or 6V if in a converter job.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements
wrote:

Quoted text here. Click to load it


I had to put in the 0,100 limits to avoid startup goofies, like teravolt spikes.
So far, LT Spice doesn't seem to mind dividing by zero.

Quoted text here. Click to load it

I used the generic LT Spice schmitt, tweaked a little. In real life, 5
paralleled HC14 or AC14 gates should drive a small mosfet pretty well.

I like the way it makes single shots after the cap is charged up. That's
probably better, by accident, than most burst-mode chips would work.

One bug is the high continuous-mode startup current, so I added a soft-start.
The ss cap will have to be discharged, of course.

I'd like to find a snubber circuit that recycles the energy, but that's probably
too complex.


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TEXT 1064 432 Left 2 !.tran 0 5m 0 10n uic
TEXT 1040 488 Left 2 ;PRETTY DUMB BOOST
TEXT 1072 544 Left 2 ;JL  June 29 2013
TEXT 648 104 Left 2 !K L1 L2 0.95
TEXT 192 624 Left 2 ;74HC14
TEXT -40 384 Left 2 ;SOFT
TEXT -48 416 Left 2 ;START
TEXT 160 504 Left 2 ;OSC
TEXT 696 168 Left 2 ;1:3






--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
Quoted text here. Click to load it

[...]

Quoted text here. Click to load it

You could also get a cheap inverting gate driver with Schmitt input,
runs that as oscillator. If it is one without UVLO you could feed it
directly off of your 9V input.

[...]

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements

Quoted text here. Click to load it

We stock LM5112, a pretty cool part. That would work. It might turn out that
there is some fet with nice specs but prefers more gate drive. Might need
another resistor to futz the duty cycle.

But it costs over a dollar! An AC14 is 10 cents!


--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
Quoted text here. Click to load it

It should cost less than 50c. Where do you buy them? Other chips:

http://www.micrel.com/_PDF/mic4416.pdf

And, if you calculate the energy savings over the next 200 years you'll
have it all back. When it has to be ral chep I use a CD40106 and a
PNP/NPN follower. Some seciton of the 40106 can be rented out.

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements
On Sat, 29 Jun 2013 14:07:45 -0700, John Larkin wrote:

Quoted text here. Click to load it

<Spice listing>

Simulation slows to a crawl as the converter starts up. Not so much a
slow, as a delayed, start. Surge current is substantially the same, just
delayed.

--  
"For a successful technology, reality must take precedence  
over public relations, for nature cannot be fooled."
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Re: Boost Converter Efficiency Improvements
wrote:

Quoted text here. Click to load it


This is what I'm seeing. Without the soft-start, the input current peaks at
about 1.6 amps.

https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/Boost_Schmitt.jpg

This run took a couple of minutes on my 5-year old HP. The soft-start doesn't
affect the sim speed much; I get around 13 PPM of real time during chargeup.


--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
On Sun, 30 Jun 2013 09:20:22 -0700, John Larkin wrote:

Quoted text here. Click to load it

That's not what I see. I see about 10 microseconds chargeup, followed by a
slowdown to a few ps/s as the converter starts, then molasses.

With, or without the soft start, current draw as the switch starts is a
tad under 5 amps peak.

Without the slow start, a run takes about a minute.

--  
"For a successful technology, reality must take precedence  
over public relations, for nature cannot be fooled."
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Re: Boost Converter Efficiency Improvements
On Sun, 30 Jun 2013 09:47:59 -0700, Fred Abse wrote:

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Sorry, mistaken, 490 microseconds chargeup.
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Re: Boost Converter Efficiency Improvements
On Sun, 30 Jun 2013 09:20:22 -0700, John Larkin wrote:

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Bingo! It was the Skyworks schottky model that was causing the problem.
It's a 2V mixer diode (BV=3), not suitable. What model were you
using? I was using the "official" model per Skyworks datasheet.

Using a Diodes inc. 1N5711, I now get what you got.

Your SMS 7621 model must differ from mine.

Must admit I prefer Joerg's soft start, though;-)

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over public relations, for nature cannot be fooled."
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Re: Boost Converter Efficiency Improvements
wrote:

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I just pulled it out of the LT Spice list. I'm not sure where it came from. The
devices aren't sorted alphabetically, so I tend to pick the first thing that
might work.

The SMS7621 is actually good to maybe 6 volts in real life. 0.22 pF. We use a
lot of them.

Quoted text here. Click to load it

It does have the startup burst bug.



--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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Re: Boost Converter Efficiency Improvements
On Sun, 30 Jun 2013 13:02:00 -0700, John Larkin wrote:

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This is what I have:

.model sms7621 D is=2.6459e-8 Rs10%.3 N=1.01 TT= 1e-11 Cjo=0.13 M=0.35 Eg=0.69 XTI=2 Fc=0.5 Bv=3 Ibv=1e-5 Vj=0.51

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"For a successful technology, reality must take precedence  
over public relations, for nature cannot be fooled."
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Re: Boost Converter Efficiency Improvements
John Larkin wrote:
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No more. It's fixed, costs one extra diode:

Version 4
SHEET 1 1920 1076
WIRE 208 48 96 48
WIRE 96 144 96 48
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 816 144 768 144
WIRE 960 144 896 144
WIRE 1040 144 960 144
WIRE 1152 144 1104 144
WIRE 1200 144 1152 144
WIRE 1328 144 1280 144
WIRE 1344 144 1328 144
WIRE 1360 144 1344 144
WIRE 96 176 96 144
WIRE 768 208 768 144
WIRE 240 240 240 144
WIRE 320 240 240 240
WIRE 464 240 464 144
WIRE 464 240 384 240
WIRE 1152 240 1152 144
WIRE 1200 240 1152 240
WIRE 1328 240 1328 144
WIRE 1328 240 1264 240
WIRE 1328 288 1328 240
WIRE 656 304 656 144
WIRE 720 304 656 304
WIRE 768 304 720 304
WIRE 96 320 96 256
WIRE 656 336 656 304
WIRE 768 336 768 304
WIRE 960 336 960 144
WIRE 304 384 272 384
WIRE 400 384 368 384
WIRE 1328 400 1328 352
WIRE 656 432 656 416
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 768 480 768 416
WIRE 960 480 960 416
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 656 592 656 528
WIRE 768 592 768 544
WIRE 960 592 960 544
WIRE 1216 624 1152 624
WIRE 1344 624 1296 624
WIRE 1360 624 1344 624
WIRE 96 672 96 576
WIRE 160 672 96 672
WIRE 272 672 160 672
WIRE 464 672 400 672
WIRE 480 672 464 672
WIRE 560 672 544 672
WIRE 688 672 624 672
WIRE 720 672 688 672
WIRE 1152 672 1152 624
WIRE 1360 688 1360 624
WIRE 272 704 272 672
WIRE 464 704 464 672
WIRE 96 720 96 672
WIRE 400 784 400 672
WIRE 400 784 320 784
WIRE 96 832 96 784
WIRE 272 832 272 800
WIRE 1152 832 1152 752
WIRE 1360 832 1360 752
WIRE 240 912 144 912
WIRE 368 912 320 912
WIRE 464 912 464 784
WIRE 464 912 432 912
WIRE 464 928 464 912
WIRE 464 1056 464 1008
FLAG 1344 144 VP
FLAG 656 592 0
FLAG 96 320 0
FLAG 720 304 DRAIN
FLAG 560 512 GATE
FLAG 768 208 0
FLAG 960 592 0
FLAG 1152 832 0
FLAG 1344 624 EFF
FLAG 768 592 0
FLAG 1360 832 0
FLAG 96 832 0
FLAG 160 672 rc
FLAG 272 832 0
FLAG 464 1056 0
FLAG 688 672 VP
FLAG 1328 400 0
FLAG 208 48 9V
FLAG 144 912 9V
SYMBOL ind2 512 160 R270
WINDOW 0 -41 56 VTop 2
WINDOW 3 -53 53 VBottom 2
SYMATTR InstName L1
SYMATTR Value 3
SYMATTR Type ind
SYMATTR SpiceLine Rser=0.06
SYMBOL schottky 1040 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 48 55 Left 2
WINDOW 3 54 83 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 800 160 R270
WINDOW 0 -32 56 VTop 2
WINDOW 3 -41 57 VBottom 2
SYMATTR InstName L2
SYMATTR Value 27
SYMATTR Type ind
SYMATTR SpiceLine Rser=0.06
SYMBOL res 528 496 R90
WINDOW 0 77 56 VBottom 2
WINDOW 3 84 57 VTop 2
SYMATTR InstName R3
SYMATTR Value 10
SYMBOL res 1184 160 R270
WINDOW 0 -38 31 VTop 2
WINDOW 3 -11 86 VBottom 2
SYMATTR InstName R6
SYMATTR Value 1m
SYMBOL cap 1264 224 R90
WINDOW 0 68 59 VBottom 2
WINDOW 3 42 -8 VTop 2
SYMATTR InstName C3
SYMATTR Value 100m
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 73 60 VBottom 2
WINDOW 3 47 -14 VTop 2
SYMATTR InstName C6
SYMATTR Value 100m
SYMBOL res 944 320 R0
WINDOW 0 -54 67 Left 2
WINDOW 3 -58 98 Left 2
SYMATTR InstName R9
SYMATTR Value 500
SYMBOL cap 944 480 R0
WINDOW 0 -46 35 Left 2
WINDOW 3 -50 68 Left 2
SYMATTR InstName C7
SYMATTR Value 30p
SYMBOL bv 1152 656 R0
WINDOW 3 -557 141 Left 2
WINDOW 0 -83 97 Left 2
SYMATTR Value V= LIMIT (0, 100 * I(R6) * V(VP)  /  ( I(R8) * 9 ), 100 )
SYMATTR InstName B1
SYMBOL res 1312 608 R90
WINDOW 0 70 60 VBottom 2
WINDOW 3 78 61 VTop 2
SYMATTR InstName R1
SYMATTR Value 1K
SYMBOL res 752 320 R0
WINDOW 0 53 70 Left 2
WINDOW 3 51 100 Left 2
SYMATTR InstName R2
SYMATTR Value 200
SYMBOL cap 752 480 R0
WINDOW 0 60 34 Left 2
WINDOW 3 56 72 Left 2
SYMATTR InstName C1
SYMATTR Value 200p
SYMBOL cap 1344 688 R0
WINDOW 0 -37 63 Left 2
WINDOW 3 -43 94 Left 2
SYMATTR InstName C2
SYMATTR Value 50n
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 80 720 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 nmos 320 704 M0
WINDOW 0 77 0 Left 2
WINDOW 3 63 35 Left 2
SYMATTR InstName M2
SYMATTR Value 2N7002
SYMBOL res 448 688 R0
WINDOW 0 47 64 Left 2
WINDOW 3 40 94 Left 2
SYMATTR InstName R5
SYMATTR Value 10K
SYMBOL zener 560 688 R270
WINDOW 0 50 33 VTop 2
WINDOW 3 -13 35 VBottom 2
SYMATTR InstName D2
SYMATTR Value 1N5369B
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 1312 288 R0
WINDOW 0 -61 48 Left 2
WINDOW 3 -59 81 Left 2
SYMATTR InstName C5
SYMATTR Value 5
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 448 912 R0
WINDOW 0 47 64 Left 2
WINDOW 3 40 94 Left 2
SYMATTR InstName R11
SYMATTR Value 10K
SYMBOL cap 368 928 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName C9
SYMATTR Value 0.33
SYMBOL res 224 928 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 0 56 VBottom 2
SYMATTR InstName R10
SYMATTR Value 10k
SYMBOL diode 544 688 M270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D3
SYMATTR Value 1N4148
TEXT 1064 432 Left 2 !.tran 0 15m 0 10n uic
TEXT 1040 488 Left 2 ;PRETTY DUMB BOOST
TEXT 1072 544 Left 2 ;JL  June 29 2013
TEXT 648 104 Left 2 !K L1 L2 0.95
TEXT 192 624 Left 2 ;74HC14
TEXT 296 1016 Left 2 ;SOFT
TEXT 296 1040 Left 2 ;START
TEXT 160 504 Left 2 ;OSC
TEXT 696 168 Left 2 ;1:3

--  
Regards, Joerg

http://www.analogconsultants.com/

Re: Boost Converter Efficiency Improvements

Quoted text here. Click to load it

Try this one. Sweet startup current curve.


Version 4
SHEET 1 1920 1076
WIRE 224 96 96 96
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 816 144 768 144
WIRE 960 144 896 144
WIRE 1040 144 960 144
WIRE 1152 144 1104 144
WIRE 1200 144 1152 144
WIRE 1328 144 1280 144
WIRE 1344 144 1328 144
WIRE 1360 144 1344 144
WIRE 96 176 96 144
WIRE 768 208 768 144
WIRE 240 240 240 144
WIRE 320 240 240 240
WIRE 464 240 464 144
WIRE 464 240 384 240
WIRE 1152 240 1152 144
WIRE 1200 240 1152 240
WIRE 1328 240 1328 144
WIRE 1328 240 1264 240
WIRE 1328 288 1328 240
WIRE 656 304 656 144
WIRE 720 304 656 304
WIRE 768 304 720 304
WIRE 96 320 96 256
WIRE 656 336 656 304
WIRE 768 336 768 304
WIRE 960 336 960 144
WIRE 304 384 272 384
WIRE 400 384 368 384
WIRE 1328 400 1328 352
WIRE 656 432 656 416
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 768 480 768 416
WIRE 960 480 960 416
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 768 592 768 544
WIRE 960 592 960 544
WIRE 1216 624 1152 624
WIRE 1344 624 1296 624
WIRE 1360 624 1344 624
WIRE 656 640 656 528
WIRE 656 640 400 640
WIRE 1152 672 1152 624
WIRE 96 688 96 576
WIRE 272 688 96 688
WIRE 656 688 656 640
WIRE 1360 688 1360 624
WIRE 272 704 272 688
WIRE 400 752 400 640
WIRE 400 752 336 752
WIRE 656 800 656 768
WIRE 272 832 272 800
WIRE 1152 832 1152 752
WIRE 1360 832 1360 752
WIRE 96 880 96 688
WIRE 160 880 96 880
WIRE 272 880 160 880
WIRE 464 880 400 880
WIRE 560 880 464 880
WIRE 688 880 624 880
WIRE 720 880 688 880
WIRE 272 912 272 880
WIRE 464 912 464 880
WIRE 96 928 96 880
WIRE 400 992 400 880
WIRE 400 992 320 992
WIRE 96 1040 96 992
WIRE 272 1040 272 1008
WIRE 464 1040 464 992
FLAG 1344 144 VP
FLAG 656 800 0
FLAG 96 320 0
FLAG 720 304 DRAIN
FLAG 560 512 GATE
FLAG 768 208 0
FLAG 960 592 0
FLAG 1152 832 0
FLAG 1344 624 EFF
FLAG 768 592 0
FLAG 1360 832 0
FLAG 96 1040 0
FLAG 160 880 rc
FLAG 272 1040 0
FLAG 688 880 VP
FLAG 1328 400 0
FLAG 224 96 9V
FLAG 464 1040 0
FLAG 272 832 0
SYMBOL ind2 512 160 R270
WINDOW 0 -41 56 VTop 2
WINDOW 3 -53 53 VBottom 2
SYMATTR InstName L1
SYMATTR Value 3
SYMATTR Type ind
SYMATTR SpiceLine Rser=0.06
SYMBOL schottky 1040 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 48 55 Left 2
WINDOW 3 54 83 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 800 160 R270
WINDOW 0 -32 56 VTop 2
WINDOW 3 -41 57 VBottom 2
SYMATTR InstName L2
SYMATTR Value 27
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 1184 160 R270
WINDOW 0 -38 31 VTop 2
WINDOW 3 -11 86 VBottom 2
SYMATTR InstName R6
SYMATTR Value 1m
SYMBOL cap 1264 224 R90
WINDOW 0 68 59 VBottom 2
WINDOW 3 42 -8 VTop 2
SYMATTR InstName C3
SYMATTR Value 100m
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 73 60 VBottom 2
WINDOW 3 47 -14 VTop 2
SYMATTR InstName C6
SYMATTR Value 100m
SYMBOL res 944 320 R0
WINDOW 0 -54 67 Left 2
WINDOW 3 -58 98 Left 2
SYMATTR InstName R9
SYMATTR Value 500
SYMBOL cap 944 480 R0
WINDOW 0 -46 35 Left 2
WINDOW 3 -50 68 Left 2
SYMATTR InstName C7
SYMATTR Value 30p
SYMBOL bv 1152 656 R0
WINDOW 3 -269 254 Left 2
WINDOW 0 -83 97 Left 2
SYMATTR Value V= LIMIT (0, 100 * I(R6) * V(VP)  /  ( I(R8) * 9 ), 100 )
SYMATTR InstName B1
SYMBOL res 1312 608 R90
WINDOW 0 70 60 VBottom 2
WINDOW 3 78 61 VTop 2
SYMATTR InstName R1
SYMATTR Value 1K
SYMBOL res 752 320 R0
WINDOW 0 53 70 Left 2
WINDOW 3 51 100 Left 2
SYMATTR InstName R2
SYMATTR Value 200
SYMBOL cap 752 480 R0
WINDOW 0 60 34 Left 2
WINDOW 3 56 72 Left 2
SYMATTR InstName C1
SYMATTR Value 200p
SYMBOL cap 1344 688 R0
WINDOW 0 -37 63 Left 2
WINDOW 3 -43 94 Left 2
SYMATTR InstName C2
SYMATTR Value 50n
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 nmos 320 912 M0
WINDOW 0 77 0 Left 2
WINDOW 3 63 35 Left 2
SYMATTR InstName M2
SYMATTR Value 2N7002
SYMBOL res 448 896 R0
WINDOW 0 47 64 Left 2
WINDOW 3 40 94 Left 2
SYMATTR InstName R5
SYMATTR Value 10K
SYMBOL zener 560 896 R270
WINDOW 0 50 33 VTop 2
WINDOW 3 -13 35 VBottom 2
SYMATTR InstName D2
SYMATTR Value 1N5369B
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 1312 288 R0
WINDOW 0 -61 48 Left 2
WINDOW 3 -59 81 Left 2
SYMATTR InstName C5
SYMATTR Value 5
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 0.6
SYMBOL npn 336 704 M0
WINDOW 0 100 35 Left 2
WINDOW 3 76 73 Left 2
SYMATTR InstName Q1
SYMATTR Value 2N4401
TEXT 1040 416 Left 2 !.tran 0 5m 0 10n uic
TEXT 1016 464 Left 2 ;PRETTY DUMB BOOST
TEXT 1040 552 Left 2 ;JL  June 30 2013
TEXT 648 104 Left 2 !K L1 L2 0.95
TEXT 192 624 Left 2 ;74HC14
TEXT 160 504 Left 2 ;OSC
TEXT 696 168 Left 2 ;1:3
TEXT 1056 504 Left 2 ;(npn soft start)



--  

John Larkin                  Highland Technology Inc
www.highlandtechnology.com   jlarkin at highlandtechnology dot com    

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