Generate pwm using ic 555
From wikiluntti
Introduction
IC 555 is an astable multivibrator (oscillator).
Frequency: The ON time is defined by the time taken to its capacitor to charge to 1/e level through pin7 resistor, and the OFF time is the discharging time of the capacitor through pin7.
Theory
Method 1
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Method 2: with diodes
555 internal design and theory
See https://www.electronicshub.org/555-timer-pwm/
and the internal circuit looks like below:
References
https://www.homemade-circuits.com/how-to-use-ic-555-for-generating-pwm/
