Demystifying Switched Capacitor Circuits

Demystifying Switched-Capacitor Circuits

82

Appendix 3.1

A SWITCAP programming example is presented here. These source codes may be

used to simulate the parasitic-sensitive bilinear SC integrator shown in Figure 3.2(b),

and to plot the frequency responses (with and without C

p1

, respectively) between 1 Hz

and 600 kHz. Furthermore, a MATLAB program is used to verify Equation (3.50). It

is assumed that the feedback capacitor C

0

= 5 pF, the sampling capacitor C = 0.5 pF,

the parasitic capacitor C

p1

= 0.05 pF, the input signal frequency f

in

= 48 kHz, and the

sampling clock frequency f

clk

= 1.2 MHz.

/*SWITCAP program*/

TITLE: SIMULATING PARASITIC-SENSITIV ...