No current sense resistor required for MOSFET switch protection

--- Nope, it ain't, but you'd like for it to be, wouldn't you, since that'd leave you on your perceived top of the heap?

Here you are, a mosquito flitting around the arena who wants to suck on the big boys, and all you've got going for you is...

Not much, from my point of view.

Care to comment?

JF

Nah, your whine has spoiled the crop.

--
Win, you old devil, are you back? ;)

Here, I need to thank you for:

                  Vcc
     t= RC ln ------------ = kRC
               Vcc - Vth  

Thank you!


JF

From RC timing that starts at V(t)=0 and rises to V(t)=Vth when the R is sourced by Vcc. Flipping it around gets back to the usual equation for that:

V(t) = Vth = Vcc*(1-e^(-t/RC))

Jon

I prefer remembering the general equation in my head:

V = (VI-VF)*e^(-t/TAU)+VF

where VI = Vinitial, VF = Vfinal, with V = desired threshold point ...Jim Thompson

--
| James E.Thompson, CTO                            |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
      The only thing bipartisan in this country is hypocrisy

Oh, well. I like to give people the benefit of the doubt, but there isn't much doubt left, I'm afraid.

*plonk*

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net

Yawn....Sleepy...Too many posts to........................zzzzzzzzzzzz

>

Ah, you're going away now. Good news.

John

If you're suggesting that one can monitor Vds of a mosfet, and when it exits its resistive region turn on a bipolar, and steal the gate drive, that's a great idea. So great it's been used for a dog's age, or maybe two.

Just be careful to turn it mostly off before Vds gets too big. A "300 watt" mosfet can explode at 100 watts if Vds is large. Switchmode fets don't like being used as linear parts.

John

Yep, riding off into the sunset. I'll post the "circuit" on my website for maximum mileage. A nanosecond of fame here just isn't woth it. You probably know the adage regarding "throwing your pearls to swines". Farewell "screwface Allison".

>

You're right, we should be more tolerant of affected fatheads.

John

What's that? Can't hear you. I know you're mumbling something but I'm "hills and vales" away by now.

>

--- "oparr" was a strange little duck who thought that he'd just turn to luck and "reveal" to the world (while keeping them furled) some "pearls" he picked up from the muck.

He wanted a pathway to fame but knew that his sojourn was lame so he thought up a plot that he thought was quite hot: not to prove, but to dictate his claim.

And so onto USENET he trolls with a tale that's soon shot full of holes 'bout a circuit so fine it was nearly divine but whose workings he kept with the moles.

"I'll _not_ share with swine types like you, my pearls." said the arrogant shrew, "But they'll be on my site, so that others might bite, and not gag on my lies, like you do."

And so he got into his hearse, and drove west for better or worse, and thought how to learn about how he could turn his ear into a fine silk purse.

JF

Dusk gave way to night as Oparr and his trusty steed made distance between themselves and the camp of the Butoski. Behind were the hills and vales of Kamora and before lay the Ameridian plains, home to Alfe the sacred river which ran through many a cavern and bottomless pit. Much had been said of its healing powers and bestowal of immortality to the greatest of the great.

Little did Oparr know that already Butoski men were singing praises to his greatness and their women writing poems and stories for their young. For they had seen his might and power, spontaneous stellar conversion, a gift from Jasofar. Thus began the legend of Oparr, The Magnificent, Last of the great Krystal warriors.

Chapter 97 of the Akashic During the reign of Jasofar the most high Planet Krystal, galaxy Arbitron (8.2 trillion light years from the Milky Way)

>

Trusty steed? Many a cavern and bottomless pit? Who wrote that crap?

You imagine yourself to be some comic book character? How old are you anyhow?

But the universe isn't that big. By about three orders of magnitude.

And Arbitron is a radio ratings agency.

John

--- "oparr" was a strange little duck who thought that he'd just turn to luck and "reveal" to the world (while keeping them furled) some "pearls" he picked up from the muck.

He wanted a pathway to fame but knew that his sojourn was lame so he thought up a plot that he thought was quite hot: not to prove, but to dictate his claim.

And so onto USENET he trolls with a tale that's soon shot full of holes 'bout a circuit so fine it was nearly divine but whose workings he kept with the moles.

"I'll _not_ share with swine types like you, my pearls." said the arrogant shrew, "But they'll be on my site, so that others might bite, and not gag on my lies, like you do."

And so he got into his hearse, and drove west for better or worse, and thought how to learn about how he could turn his ear into a fine silk purse.

JF

--- Traveling the Ameridian plains for years, Oparr eventually crossed into the land of Usenet and ventured into the village of sed, a gathering-place of fierce warrior-philosophers who practiced the art of debunkery.

Within hours of his pretense to glory, Oparr's words were shown to be false, his honor besmirched, his credibility ruined, and thus ended the legend of Oparr, forever after known as Oparr of the Forked Tongue.

JF

[snip]

Who apparently lives in or near Chandler, AZ.

If someone can locate his supposed website I'll track down his employer :-) ...Jim Thompson

-- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at

| 1962 | The only thing bipartisan in this country is hypocrisy

AZ_Nomad? (or whatever its name)