Rise Time and Fall Time
Posted by: slawik
on
Hello!
I doubt whether I understand the parameters Rise Time and Fall Time.
In the datasheet, such as a HX Family, said that these parameters are measured in a Typical Flyback Converter Application.
There are two questions:
1) Rise Time - this is the rise time of the current from zero to maximum when the MOSFET turn on and Fall Time, respectively, is the current decrease time at MOSFET turn off?
Or Rise Time - this is the rise time of the voltage Vds when the MOSFET turn off and Fall Time is the voltage decrease time when the MOSFET turn on?
2) These parameters apply only to the CCM?
Rise Time and Fall Time refer to how fast the MOFSET integrated into the IC can switch on and switch off. There are a number of factors that come into play.
When the MOSFET turns ON and the voltage (VDS) across the MOSFET falls to zero, the time it takes the voltage to go from 90% to 10% is called the Fall Time.
When the MOSFET turns OFF and VDS goes from zero to Vmax, the Rise Time is the amount of time that it takes for VDS to go from 10% to 90% of the final voltage.
-The Traveler