Yes, you can do it.
That small of a bias change won't really get you much.
You'll still have an AB amp, with crossover distortion happening at a different signal level.
Might even put the cross-over at a bad signal level.
That small of a bias change won't really get you much.
You'll still have an AB amp, with crossover distortion happening at a different signal level.
Might even put the cross-over at a bad signal level.
Eva said:
According to the data sheet , the Toshiba 2SK1529 transconductance (Gm) at 100 mA drain current is 0,5 S.
As the output impedance of a mosfet follower is 1/Gm, resolving the output impedance become 2 Ohms.
If the output transistor current gain, in even only 50, the open loop output impedance become 2 /50 = 0,04 Ohms certainly a remarkable result and this value is attained , before any overall feedback.
In a source follower ( case in discussion), this 1 nF capacity is effectively bootstrapped and we end up with a much lower input capacitance.
No, this is due to gate capacitace being a dynamic parameter in MOSFETs. Gate capacitance increases and decreases depending on things like Vds and Id. But the amount of charge stored does not change unless some current flows into or out of the gate.
Thats why the gate will sink or source current if you try to keep Vgs constant while changing Vds and/or Id. Also, Vgs will change on its own if you leave the gate open and change Vds and/or Id.
Funny, isn't it?.
In switching circuits you may happen to be sourcing 500mA to a gate during 100nS while not observing any Vgs change at all.
Thats why the gate will sink or source current if you try to keep Vgs constant while changing Vds and/or Id. Also, Vgs will change on its own if you leave the gate open and change Vds and/or Id.
Funny, isn't it?.
In switching circuits you may happen to be sourcing 500mA to a gate during 100nS while not observing any Vgs change at all.
Thanks, I understand now, like a capacitive microphone it creates signal, be it voltage or current. Or like a varactor.
Do you think it is very important factor in linear applications?
regards 😉
P.S. sorry for off topic questions here.
Do you think it is very important factor in linear applications?
regards 😉
P.S. sorry for off topic questions here.
I think it is very important for linear applications, but I want to see the input current waveform of a MOSFET driving a resistor in class A at 10Khz with considerable Vds and Id swing in order to be sure 😀 I'll try it as soon as I can and I'll post the waveforms.
Don't try simulation, my version of PSpice and/or its models (the stuff that comes with Orcad 9.1) is so lousy that it simulates constant capacitances... 🙄
Don't try simulation, my version of PSpice and/or its models (the stuff that comes with Orcad 9.1) is so lousy that it simulates constant capacitances... 🙄
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