Graphical Analysis Thursday, April 08, 2021 2:30 AM Analysis of simple diode circuits Page 1 Analysis of simple diode circuits Page 2 Analysis of simple diode circuits Page 3 Small-signal Analysis: The concept of dynamic resistance Thursday, April 08, 2021 3:01 AM • The swing of the signal is a small fraction of its dc component, giving the name small signal. • With small signal assumed, the circuit operates over a small range of its possible operating range. • The diode characteristics is assumed to be linear over this range and the diode can be replaced by a single resistance and we can apply standard circuit analysis techniques. • As a first step, we set • The diode in this range can be replaced by a resistance equal to the inverse of the slope of the linear region. • This resistance is called the dynamic resistance Analysis of simple diode circuits Page 4 • The dc calculation is carried out graphically and the small signal analysis is done using Ohm's law. rd is evaluated from the diode characteristics at the Q-point Analysis of simple diode circuits Page 5 Analysis of simple diode circuits Page 6
