Internal resistance of mosfet circuit

Thread Starter

Romsha

Joined Nov 29, 2013
17
what does 'looking into' mean when we are calculating the resistance. For example considering a T equivalent circuit of common source amplifier. The author states that the resistance between gate and source looking into Source terminal is Rs while looking into the gate terminal the resistance between source and gate is infinite. I have attached a picture of the circuit for reference.
Please help me understand.
Thank you
 

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wayneh

Joined Sep 9, 2010
16,398
That wording implies a directionality to the resistance, which doesn't make sense to me. The gate is like a small capacitor. It passes current briefly upon charging or discharging, but no steady state DC current.
 

cmartinez

Joined Jan 17, 2007
7,022
The author states that the resistance between gate and source looking into Source terminal is Rs while looking into the gate terminal the resistance between source and gate is infinite
It would help if you were to tell us the name of said author, and in what book you found that quote, if possible.
 
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