IC555 Oscillator

Objective

Wire an astable multivibrator circuit using IC555, measure the frequency and duty cycle of the output.

_images/osc555.svg _images/ic555-screen.png

Circuit is shown in figure. The frequency is given by f = 1 /(\ln 2 \times C \times (R_1 + 2 R_2). The HIGH time is given by \ln 2 \times C \times (R_1 + R_2) and LOW time by \ln 2 \times C \times R_2.

Procedure

Discussion

The output waveform is shown in figure. Change the value of resistors or the capacitor, and compare the frequency and duty cycle with the calculated values.