// Exa 2.6 clc; clear; // Given data // Referring circuit shown in Fig. 2.11(a) B=200; // Current gain Icq = 100*10^-6; // Amperes ADM = 500; // Voltage gain for differential mode signal CMRR_db = 80; // in dB(Common mode rejection ratio) // Solution // Since gm = Icq/Vt therefore, gm = Icq/(25*10^-3); // for Vt = 25 mV printf('Using Eq. 2.50, we have ADM = -gm*Rc so from this we get Rc as '); Rc =abs(- ADM/gm); printf(' %d kΩ. \n ',Rc/1000); printf('Since CMRR = 80 dB converting it into non dB value so CMRR = '); CMRR = 10^(CMRR_db/20); printf(' %d. \n ',CMRR); printf('Using Eq. 2.55, we get value of Re as '); // CMRR = 1+ 2*gm*Re; therefore Re = (CMRR-1)/(2*gm); printf(' %.2f MΩ. \n ',Re/10^6);