What is a driver circuit referring to MOSFETs?

[Sputnik]

New to MOSFET!

I am new to MOSFETs and have never used them. What is a "driver circuit" that I read about quite often when MOSFETs are involved and is it completely necessary? Or do MOSFETs work similarly to transistors?

Thanks
Sputnik :idea:

 

[VVV]

Re: New to MOSFET!

Well, the MOSFET works much like a transistor, but there are differences.Check out this document. It's old, but you can get an idea: www.onsemi.com/pub/Collateral/AN913-D.PDF

MOSFET drivers are used to speed up the switching action. Although they do not require a static drive current, MOSFET's have relatively large capacitances, which need to be charged/ discharged when turning on/ off the MOSFET. Charging/ discharging these capacitances requires a lot of dynamic current. This current is provided by the MOSFET driver.
A MOSFET driver is in fact an IC with a push-pull output stage, capable of sourcing and sinking the large current the MOSFET requires for fast switching.

 

[IanP]

Re: New to MOSFET!

More info you can find here:
**broken link removed**
another good source:
**broken link removed**

 

[masoudk_81]

Re: New to MOSFET!

Hi

you can find many topics about mosfets on the internet, you can find many drivers about them on the internet. i have used ICL7667 and it was good for me. you can try it.

masoud

 

[xiang]

Re: New to MOSFET!

It's depend on how big input capacitance for your MOSFET and how fast your circuitry is. If just a small MOSFET and switching frequency <100KHz, a simple TTL gate should be OK.

 

[lastdance]

Re: New to MOSFET!

Mosfet drivers are normally employed in switching regulator to improve the efficiency, this is because of the reduction in switching losses arising as a result of shoot thru if your charging/discharging edge is slow.
therefore, u need to evaluate your system before deciding to invest in a mosfet driver or not.

 

[rongli]

New to MOSFET!

I think a driver means amplified the signal's drive ability.