small signal diode modelling i understand what it is but when i get asked a question like:(adsbygoogle = window.adsbygoogle || []).push({});

if vin(t)=2.5+cos(2*pi*100*t) for 0<t<30

use the small signal model of the diode to predict the output voltage of the circuit i have added. assume the opamp is ideal R=2000 Is=10e-16

so i know that the small signal equation is

id=(ID/VT)*vd where VT=0.0252

now since the opamp is ideal zero current is drawn in and since the configuration is in the inverting configuration then Vout=-vD

now i know i have to somehow dervive and expression for Vout using the small signal diode model equation which is

id(ac current)=(ID(dc current)/0.0252))*vd(ac voltage)

i also know that ID=Is*e(vD/VT)

=(10e-16)*e(vD/0.0252)

subbing into the small signal diode model equation

id=((10e-16)*e(vD/0.0252)/0.0252)*vd

and now i get lost and stuck because i dont know what to do or if i am doing the right thing in order to derive and expression for vout using the small signal diode model

please help!

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# Small signal diode modelling

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