Help with MOSFETs
Help with MOSFETs
(OP)
Hi,
Using power Mosfet MGSF1N03LT1 (On Semiconductor), the FET takes a long time to turn off (1.2 microsecs.). Why is this?? I need for it to turn off quicker. Any suggestions on different Mosfets that will turn off quicker with the same characteristics as the On Semiconductor part??
Thanks,
swb1
Using power Mosfet MGSF1N03LT1 (On Semiconductor), the FET takes a long time to turn off (1.2 microsecs.). Why is this?? I need for it to turn off quicker. Any suggestions on different Mosfets that will turn off quicker with the same characteristics as the On Semiconductor part??
Thanks,
swb1





RE: Help with MOSFETs
TTFN
RE: Help with MOSFETs
swb1
RE: Help with MOSFETs
Keith Cress
Flamin Systems, Inc.- <http://www.flaminsystems.com>
RE: Help with MOSFETs
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"It's the questions that drive us"
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RE: Help with MOSFETs
Keith Cress
Flamin Systems, Inc.- <http://www.flaminsystems.com>
RE: Help with MOSFETs
You need hi-current driver to drive the gate fast
enough. If the Rout is high, the R*C time constant
will slow it down.
Plesae read FAQ240-1032
WEB: <http://geocities.com/nbucska/>
RE: Help with MOSFETs
Repeating the above question... what's your drive circuit like?
RE: Help with MOSFETs
FETs need to establish an electric field to control current flow.
As you may remember from physics, the voltage on a capacitor doesn't change instantly, you have to transfer charge for the voltage to change. The more current your driver can source or sink into/out of the gate, the faster the voltage will change on the gate and the faster the FET will turn on/off. There are other parasitic capacitances in the FET as well, but the gate-to-source capacitance is usually the one that lengthens switching time considerably.
RE: Help with MOSFETs
swb1