Question

Circuit Analysis

Vcc +Vcc 10 k2 R3 1kn 4 1 k2 Voi 7 555 A oVo 3 555 2 R4 10 kn R2 2 1 MQ 5 5 6 C1 1 F C3 0.1 uF C4 10 nF C2 10 nF I Figure Q2 4 Figure Q2 shows an oscillator circuit using two 555 timers. Assume that the reset pin is active low. When the switch is opened: (i) Draw the output waveform (V01) of Timer A indicating clearly the ON and OFF time, and calculate the frequency of oscillation of Timer A (4 marks) (ii) Obtain the duty cycle of Timer B. (3 marks)

Answer 1

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