Description: In the MOSFET OFF in order to guarantee the charge state grid fast xie put, this time the resistance must be as low as possible, this is also the reason Rsink < Rsource. Usually in order to guarantee quick xie put, can be in a parallel Rg diode. When xie put resistor is too small, because the inductance of the reasons go line can also cause resonance (so some application will also be in the diode crosstalk in a small resistance), but because of the diode s reverse current not conduction, at this time and participate in reverse Rg resonance loop, so can inhibit the reverse resonance peak. The diode usually using high frequency small signal tube N4148 1.
In actual use need to consider the MOSFET discharge gate has a capacitance Cgd extremely, the effects of the MOSFET ON Rg but also to Cgd when charging, will change voltage up slope, OFF VCC to Cgs charging through Cgd, this time must ensure that the charge ON a rapid Cgs OFF, otherwise, it will lead to the MOSFET abnormal conducti
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