Sure--it's a tradeoff between gradients and complexity. The problem it's intended to address may be one you don't need to worry about, namely the way the spatial heating distribution of the FET+resistor approach moves around depending on the dissipation.
If the temperature slew is sufficiently slow, or if you aren't sensitive to the gradients changing shape with time, KISS is certainly the way to go.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
As long as the T-loop is not too fast :^) I do this trick with diode laser where you modulate the diode current and the grating angle in phase. At sorta 1-10 Hz rates. If the thermal loop was too fast it would fight the current modulation.
Our interaction does seem to have degenerated from the one to the other - a nd since I'm now complaining about it, I've managed to demonstrate the capa city to effect this discrimination in this particular case.
But you do want to have the last word, even when that last word hasn't got much to do with the subject under discussion.
I object to incorrect posts. The skewering is incidental.
Odd. Your posts are rarely incorrect, and if you make an error - as we all do from time to time - I remain well aware that you are one the most reliab le sources around here.
The proportion of political rubbish rose. You'll still find helpful and con structive posts from me, from time to time, but they represent a smaller pr oportion of my output. I worry more about anthropogenic global warming than I used to, and John Larkin reposts more denialist propaganda than he used to.
I'm not interested in looking like anything in particular - I'm not looking for potential customers any more, and I've never been someone to flatter p otential allies, no matter how much I admire their electronic skills.
But if it were that fast, you could modulate the setpoint instead. ;)
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
Senility? Some of us "age" retaining our "think like an 18 year old" (but then I falls asleep ;-) minds" , others, like Slowman... ...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Most transistors, bipolar or fets, will melt solder before they fail. Mosfets go berzerk at a bit past 300C, basically turning on with no gate drive. They tend to fail hard a little past that.
--
John Larkin Highland Technology, Inc
picosecond timing laser drivers and controllers
jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com
There's a strong tendency for all of us to turn into caricatures of ourselves as we age. Fighting it helps (hint, hint).
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
But Slowman's circuit comments are mostly just so f**king dumb... "emitter _pushing_", and edward.ming.lee's, "Growing wafers takes time and money".
Sheeeesh! How's an ol' fart to cope with such nonsense ?>:-} ...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Which is ironic, because flies are actually much more attracted to vinegar (it's a product of biological decomposition, after all). Our parents lied to us; and taking the analogy further: the effectiveness of trolls on the internet and elsewhere bears this out.
Yeah, that's good when you have more power to dissipate than the transistor can handle -- a load dump for example. You can about double the capacity for a given transistor, saving some bucks on heatsinking and all that.
I'll be interested to see your experimental results on YouTube. ;)
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
hobbs at electrooptical dot net
http://electrooptical.net
Also, that was an interesting workaround. OE, in its infinite wisdom -- of course -- is not RFC compliant, so it happily stacks References in the header. Which you can't edit from within OE. So at just the right stage in this highly-stacked thread, it sends the massive line, and eternal-september in my case bounces it (441 error).
The workaround I saw was, save the original message, edit the plaintext in Notepad to remove extra references, then reply to that.
(If these replies end up in some bizarre place in your newsreader's threading, I guess you can actually blame it on me personally?)
In over a decade, this is the first time I've ever seen this happen. Weird.
Tim
--
Seven Transistor Labs
Electrical Engineering Consultation
Website: http://seventransistorlabs.com
"Tim Williams" wrote in message
news:mi8jtc$1h4$2@dont-email.me...
> "Phil Hobbs" wrote in message
> news:rKGdnYWVG8dgUtrInZ2dnUU7-N2dnZ2d@supernews.com...
>>>
>> I'll be interested to see your experimental results on YouTube. ;)
>
> No need; others have reproduced it. :)
> https://youtu.be/1hb9HMhwvio?t=1m28s (or watch the whole thing)
>
> As for the troll aspect, YouTube also provides proof in the famed quality
> of
> their comments. ;-)
>
> Tim
>
> --
> Seven Transistor Labs
> Electrical Engineering Consultation
> Website: http://seventransistorlabs.com
>
Yep. I just tried the scheme of taking a 2-liter soda bottle, cutting off the top, inverting it into the bottom (funnel-style) and filling it part way with vinegar and sugar mix... works fairly well.
The problem seems to be that the flies only come when we are on the patio, doing a steak :-(
Next trial... fill with Coke and some raw hamburger... I suspect that will be the ticket. ...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
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