## Astable waveforms

Charge time (output high)

t1 = 0.693(Ra+Rb)C

Discharge time (output low)

t2 = 0.693(Rb)C

Total period

T = t1+t2 = 0.693(Ra+2Rb)C

Frequency of oscillation

f = 1/T = 1.44/(Ra+2Rb)C

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