The collector-coupled monostable multivibrator is shown in Fig. 8.1. When compared to an astable multivibrator as shown in Fig. 7.1, it is evident that the output from the second collector to the first base is through a resistance R1. Hence, this circuit has one stable state and one quasi-stable state.
As a negative voltage is connected to the base of the first device, it is possible that Q1 may be OFF. In the stable state, let Q1 be OFF and Q2 be ON and in saturation. Therefore:
VC1 = VCC VC2 = VCE(sat) VB2 = VBE(sat) = Vσ
The capacitor, C now tries to charge to VCC through RC of Q1 and a small input resistance of Q2, as shown in Fig. 8.2. As t→∞, this voltage reaches VCC. To change the ...