hello, im using texas instruments UCC27519DBVR (low side) gate driver ic for driving my mosfet at 35khz im generating 35khz pwm with a 555 timer and both ic's generate perfect square wave (12v) but mosfet is not turning off at high frequencies. I tried 10nC and 70nC gate charge mosfets but both did the same thing 
. I checked everything and nothing seems wrong please help im losing my mind 
Already lost it, if you think anyone is going to be able to help you without seeing your schematic! 
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gate discharger
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i tried it with a schottky diode and 1n4148 but it didnt work
What do you have connected between the drain of the MOSFET and the 12V supply?
(Where you have a box labelled oscilloscope.)
It is the load connected between drain and 12V that pulls the drain high.
i have a multimeter that has a built in oscilloscope. i tried connecting a 12v led and it worked, it doesnt work without the load connected i think beacuse when i disconnect the load it stops working. Thanks it finally worked 
What load is on the drain of your Mosfet?
Right. You need a load to pull-up the voltage when the MOSFET is off.
Great. Just so we can be sure, can you explain back to us why you got only a tiny variation in the scope readings in your original circuit?
i didnt understand your question, the scope readings was almost reading perfect 12v dc
Is your "555" the bipolar version (NE555, LM555) or the CMOS (7555, TLC555) ?
You must put a resistor between 12Volts and the Mosfet Drain. 1K should do it.
You see the mosfet has two states (the way you are using it) either Very low resistance or open circuit.
Then connect the scope common to your circuit common and the drain.
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This is essential. Transistors (including MOSFETs) are often referred to as "switches", but electrically speaking, they're not really that. They can be put to use in switching applications, evidently, but the "switch" analogy has led many astray who start out in the field of electronics.
thanks i understand
cmos 555 timer
