IGNOU BPHET 143 2026 - Design an astable multivibrator using IC 555 to generate the

Question

Design an astable multivibrator using IC 555 to generate the square wave of 20 kHz frequency.

19 Jan 2026

Answer :

Word Count : 272

An astable multivibrator using the IC 555 can be designed to generate a continuous square wave of 20 kHz by configuring the timer in its free-running mode. In this configuration, the IC alternately charges and discharges an external capacitor through two resistors, producing a rectangular waveform at the output pin (pin 3). The essential components required are two resistors (R_A) and (R_B), and a timing capacitor (C), connected between the discharge pin (pin 7), threshold and trigger pins (pins 6 and 2), and ground. The frequency of

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