MOSFET Driver circuit required??

Does the following MOSFETs need a Driver?? I'll be using a micro-controller to generate PWM.. If we need the driver,can you suggest some driver IC's.
1.STP190N55LF3
2.STP80PF55

mosfet driver circuit
Google it

dselec said:

mosfet driver circuit
Google it

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Am asking if I need to use a Driver Circuit/ Driver IC for the following Device. I went thru the Data sheet of the above mentioned Devices. The Gate Threshold Voltage is given as 4Volt. So when I use Microcontroller the logic High would be greater than 4.5Volt. So from that Info I could not conclude.

Search for logic level devices. These have lower threshold and are suitable for 5V operation.

http://forum.allaboutcircuits.com/showthread.php?t=16578
**broken link removed**
http://www.nteinc.com/Web_pgs/LL_MOSFET.html

You can use a driver like TC4427
www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010672

A driver will ensure fast switching of the mosfet.

Alex

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Another idea is to use a smart switch which is a mosfet with driver in one case

Yes it can be used direct but not recomemded.... cause if the fet fails and it FAILLLLLLLLLLLLLLLLLS. every thing might fail your cpu your computer and the sky is the limit.
many driver have internal op-to isolation circuits so use isolated driver or use simple op-to at mcu output.

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The problem is not the isolation but the high currents needed to ensure fast switching of the mosfet.

What high current ? gate needs pico amps current .

In that case can you explain the difference in output of the circuit in this post https://www.edaboard.com/threads/224546/#post957564 ?

U mean the charge current problem it depends on fet type ill check out the input cap for the slow irf540 mosfet in contrast to the stp designated for motor cntrl.
anyway we r still missing info about what is his project...al we know he wants pwm... what freq ??? range ??? pwm for what ??? duty cycle min/max ??
more if he uses opto it will ease your mind and mine as for charge and isolation.
ther is a problem ggeting high curent and fast switching to get both ...one may have to sell his shirt and pants and some more:-D

To recommend a driver, more details about the project must be required. If all that is required is on/off slow switching, one transistor may be enough.

For high frequency driving a driver should certainly be used - be it a regular POWER MOSFET or a logic-level MOSFET. At high frequencies, quite a lot of current must be provided to the gate (in milliamps, maybe hundreds depending on the frequency). Also, to drive a POWER MOFSET to saturation to ensure minimum loss, >8V must be used to drive the gate. And for high frequency, high speed switching is also required, which makes the driver slightly more complex.

The configuration of the MOSFET must also be known. Depending on the frequency and configuration, you have to choose a driver. Some common drivers are TC42X, TC442X (eg TC427, TC4427), IR211X (eg IR2110, IR2112, IR2113), L638X (eg L6385E, L6384), NCP5181, TLP250, HCPL3120, etc.

Hope this helps.
Tahmid.