Because of its dependence on vD, the junction capacitance Cj is nonlinear. To simplify the calculations it is often convenient to work with the equivalent capacitance Cj(eq) that, in response to a...

Because of its dependence on vD, the junction capacitance Cj is nonlinear. To simplify the calculations it is often convenient to work with the equivalent capacitance Cj(eq) that, in response to a voltage change DVD 5 VD2 2 VD1, displaces the same amount of charge DQj 5 Qj (VD2) 2 Qj (VD1) as Cj , or DQj 5 Cj(eq)DVD 5 ∫VD1 VD2 Cj (vD)dvD (a) Calculate the above integral using and show that Cj(eq) 5 ( VD2 2 VD1) 3 (1 2 m)) 3 [( 1 2 VD1 0 ) 12m ] (b) With reference to calculate Cj(eq) for vD changing from VD1 5 22 V to VD2 5 10.6 V, and compare with the approximation Cj > Cj0 made in the text.