Hi all,
I am just trying a design ac switch with mosfets which are connected as common source. Mosfets will drive 16.2A load in normal conditions. When I try to drive 10 ohm load with 162V (peak, 400hz), as you can see in picture 1, there is no problem in load voltage. ( Green wave : Load Voltage, Red wave : Gate-Source Voltage)
I just try to increase load to 100k, I saw the almost 162V on load without gate firing. What is the reason of this ? Leakage current, drain-source parasitic capacitance etc.. and How can we handle this problem ? Is this really problem ? In addition, frequency is affecting the load voltage in off-state.
By the way, I saw the same thing on real circuit, not just a simulation.
I am waiting your kind comments,
Thank you,
I am just trying a design ac switch with mosfets which are connected as common source. Mosfets will drive 16.2A load in normal conditions. When I try to drive 10 ohm load with 162V (peak, 400hz), as you can see in picture 1, there is no problem in load voltage. ( Green wave : Load Voltage, Red wave : Gate-Source Voltage)
I just try to increase load to 100k, I saw the almost 162V on load without gate firing. What is the reason of this ? Leakage current, drain-source parasitic capacitance etc.. and How can we handle this problem ? Is this really problem ? In addition, frequency is affecting the load voltage in off-state.
By the way, I saw the same thing on real circuit, not just a simulation.
I am waiting your kind comments,
Thank you,
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