... right? Try adjusting the little screw on the probe.
You also have to be careful about scope overload when looking at this type of thing. Many scopes can take a long time to recover from the overload that occurs "off-screen"
kevin
AlwaysWrong, DI bought them out some time back and ditched a lot of the nice stuff.
100 us sounds fast to be thermal. But could be.
Lots of scopes recover poorly from gross overloads.
Scope probe compensation?
John
Figures that I get jammed when the electronics take me into the semiconductor thermal physics. As soon I find myself crossing into another field of expertise, that's when the trouble begins.
Getting there..
Thanks.. Will watch out for that.
groan... Was scope compensation.. It's always the dumbest thing to blame over here.. Never some exotic complex little known phenomenon to go oooo ahhh over.
That's pretty much what my wife said after she found out that I had used silver wire and solder to put a button back onto a shirt :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
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Just get a "Buttoneer" and then you can play engineer and attach buttons better than sewing them on ;-) ...Jim Thompson
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Help save the environment!
Please dispose of socialism properly!
I hope it wasn't a black shirt because it would clash. ;-)
Nope, dark blue :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Oh, that's much better. ?-/
He can't blow up any buttons that way.
-- Offworld checks no longer accepted!
Not many scopes recover cleanly from gross overload. And if you're looking for something small, like Vds in saturation, just after a big D-S voltage, both the scope and the probe can fool you.
Some of the old Tek letter-series (W, Z) plugins, and the 7000-series stuff (7A13, 7A22) have astounding overload recovery.
I tested a lot of power fets so that I could run realtime junction temperature simulations in a couple of big power amps, to push as much performance out of the fets as possible.
ftp://jjlarkin.lmi.net/ExFets.jpg
Most of them, on a heat sink, behaved roughly as if they had sort of a
1st order, 100 millisecond thermal time constant.John
That depends entirely upon the consumption of marzipan, pound cake, cheese cake, stollen and all sorts of other goodies. Comes a point where the button flies right off the shirt again upon a wee stretch :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Buttons without sound effects!!? Not in Joerg's world!
Ed
That's just popping a button. Where are the flames & shrapnel?
-- Offworld checks no longer accepted!
That comes when the button and the piece of silver wire lands in the shortwave power amp that I used to sometimes run "open cockpit" ... zzzt ... *PHOOMP*
But it was always other stuff that did that. The loudest bang was an electrolytic, back when I was a kid and didn't have the foggiest about ripple current limits and stuff. Took off and made a crater in the ceiling plaster, then upon return from its brief orbit a smolder hole in the carpet.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Dunno what I'd do without my 7A13s.
The relays can be troublesome now they're old.
--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)
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