On Mon, 18 Nov 2013 20:02:44 -0700, Jim Thompson
wrote:

On Mon, 18 Nov 2013 18:34:01 -0800, John Larkin
wrote:

On Mon, 18 Nov 2013 17:47:13 -0600, amdx wrote:


...Jim Thompson

Moron. A PCB trace, or a wire, isn't an inductor, it's a transmission
line. And a mosfet isn't an ideal switch.

According to your model, every mosfet always blows up from its own
wirebond inductance! Or from any drain trace, even if the load is
resistive!

(Thompson + inductors) dependably = (stupidity)

No amount of bloviation will cover your ignorance... wiring out to a
solenoid or relay before the catch diode will give you grief.

No matter how many times you bloviate.

...Jim Thompson

Using your idiotic simulation, I suppose so. Good thing I don't use
your idiotic simulations.

25 kilovolts! Hilarious! I wish I could make a 25 kilovolt boost
conveter from a 2N7000!

It was to make my point... after all I did say, "Wiring inductance
_between_device_and_catch_diode_ can cause voltage spikes, depending
on device TURN-OFF SPEED... "

Slower times and less inductance will, of course, produce a smaller
spike... but there WILL STILL BE A SPIKE. And CDG of a power FET will
help slow things down... perhaps enough that the dwell time in the
gate charge plateau region will slowly kill you instead.

Sometimes I feel sorry for you, being manic-depressive has got to be a
burden on an otherwise (allegedly) productive person.

But then that other part of your personality springs forth, you know
the part I mean, the PLUPERFECT ASSHOLE SIDE. Then I lose my
sympathy, and rank you right up there in that class of pompous
ignorance alongside Phil Allison and Bill Slowman.

...Jim Thompson

Boys, I don't mind a little disagreement, but Jim!
Putting anyone in the same category as Phil Allison,
shame, shame on you, that's a low blow.
Mikek


He gets abusive every time he figures out that he's wrong.

A PCB trace, or a wire, isn't an inductor: it's a transmission line
with some Zo. The drain voltage won't fly up more than Id*Zo, and will
fly up much less for practical cases.

Only if it's over a ground plane. Dummy.

...Jim Thompson

A trace or wire not "over a ground plane" has infinite Zo? It's a pure
inductance?

Gosh, Thompson teaches us something new every day. Generally wrong.


--

John Larkin Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
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