what is pinch -off voltage?

Answer 1

It is a characteristic property of a field-effect transistor, the gate-to-source voltage that causes the channel to "pinch off" and allow no current to flow source to drain. This voltage varies FET to FET based on the design.

Answer 2

I can't believe you're asking that question because it has to do with vacuum tube operation. You probably mean something else, but I'll tell you what I know anyway and let you decide if it's relevant to your situation.

Inside vacuum tubes called triode, tetrodes, and pentrodes there is an internal structure (a mesh of wires) called a grid. When the cathode is red-hot and emitting electrons and the anode is at a high positive potential electric current is said to travel from the anode to the cathode. Actually, negative electrons are flowing from the cathode to the anode. The grid structure is located between the cathode and the anode and as the voltage on the grid is driven negative the flow between the cathode and anode is diminished. The more negative the grid voltage, the less current flows through the tube. Eventually a point is reached when no current flows. The voltage on the grid when this occurs is called the pinch-off voltage. It's a parameter that changes according to the physical dimensions of the tube's internal components.

Now that I've seen the other answers I have to agree that it is also a property of field effect transistors. I guess I didn't recall that detail because I first learned it with vacuum tubes.

Answer 3

It refers to a field effect transistor. It's the voltage (gate to source) where the condition channel disappears and no appreciable current flows through the device.

Answer 4

...you mean like to Pinch one off,
Back one out
Backing the big brown motorhome out of the garage
Baiting the trap
Becoming the porcelain assassin
Black Snake playing peekaboo
Blasting a dookie
Blinking
Blow one out
Blow the load
Boo-Boo
Boom Boom
Bomb the porcelain sea
Building a log cabin
Burn a mule
Bust a crap
Caca
Carpet Bombing Afghanistan
Chocolate time!
Cooking butt pudding
Cripping a crapple
Crowning
Curling one off
Cutting rope
Deceiver of Farts
De-corking the borking
Deucing
Dirty squirties
Disco dump
Doing brown
Doing some spring cleaning
Dominating
Doo-Doo
Doodey
Download a brownload
Dr. Benjamin Fartlin
Dropping a dook
Dropping a bomb
Dropping a deuce
Dropping a hoopsnake
Dropping a jolst
Dropping a load
Dropping a mud monkey
Dropping anchor
Dropping bass ("base" as in the opposite of treble. Not the fish.)
Dropping logs
Dropping some friends off at the pool
Dropping the Browns off at the Super Bowl
Dropping the kids off at the pool
Dropping the Mexican Boll Weevil
Dropping the weights
Dropping wax
Faxing a **** to the toilet machine
Feeding the seagulls
Feeding the shitehawks
Feeding the toilet
Fertilizing the plants
Filing some papers
Filling the bowl
Fire away
Freeing my chocolate hostages
Getting a load off my mind
Giving birth
Giving birth to a chocolate baby boy
Giving birth to a healthy brown baby
Giving birth to the black eel
Giving birth to the Spineless Brownfish
Giving birth to an African
Giving the cleaner something to think about
Going Boom Boom
Going poop
Going to meet Jim Davidson
Going to number two
Going to have a talk with Mr.Hanky
Growing a tail
Hanging a rat
Hungry Hungry Hippos
Having a Code Brown
Kurt Bevacqua
Launching torpedoes
Laying a brick
Laying a brownie
Laying a cable
Laying a chocolate hot dog
Laying a Hank
Laying a turd
Laying some wolf bait
Leaving a burnt offering at the porcelain altar
Lengthening the spine
Letting loose
Letting the toilet know who's boss
Letting the dogs out
Lift tail
Logging
Logging into the toilet and making a huge download
Logging out
Load your pants
Lose some weight
Making a tail
Making an appointment with Dr. John
Making a deposit in the Porcelain Bank
Making gravy
Making logs
Making waves
Makin' bears
Monopoly!
Montezuma's Revenge
Parking the dark horse
Pass Legislation
Pebble-dashing the porcelain
Peeing out of ***
Pinching a yam
Pinch-hitting for Kurt Bevacqua
Poo-Poo
Poopsicle
Poopy Doo
Poppin a gooky
Prairie Dogging
Praying for rain
Producing some output
Pump a clump of dump out of my rump
Punching a growler
Punishing the porcelain
Punishing the toilet
Put food in the dog's water
Releasing a depth charge
Releasing a Dungbomb
Releasing the hostages
Releasing the Kraken
Releasing a Butt Dragon
Ride a pony and trap
Ring of fire
Sacrificing to the Toilet/Porcelain god
Saturday morning special
Scatter bombing
See a man about a horse
Showering the room with roses
Shtounga
Slopping gruel in Oliver's bowl
Southsider
Speaking with the arabs (When whoever is listening asks "what" the toiletee replies "Mustapha Crap!")
Spray-painting the porcelain
Squeezing out a fudge dragon
Squirt juice
Stalling a brown sedan
Studying one's Process Design notes (refers to Environmental Engineering Process Design, a course taught to civil and environmental engineering undergraduates and that deals with, among other topics, the design of wastewater treatment facilities)
Taking a brew
Taking a crap
Taking a dump
Taking a Nixon
Taking a poo
Take a ship
Taking a slam
Taking a Tarzan (crapping in the woods/forest)
Taking the Browns to the Superbowl
Taking the Cosby kids to the pool
Taking the morning curl
Throwing up backwards
Tuesday Afternoons
Turtle time
Unlikely Traveler (Defecation, usually on vacation, when you defacate in your pants away from a toilet)
Unload
Unloading a batch of cigars
Unloading a 3-coiler
UH-OH!
Visiting Boston
Vote for president.
Take a Critical Ambient to the Lab

Answer 5

IN response to the above answerer...

That's why FETs and triodes have the same "feel" when you put them in audio circuits.