IC 555 Timer
IC-555 Timer is a versatile Monolithic timing circuit that can produce accurate and highly stable time delays or oscillations. It can be used as an Astable and Monostable multivibrators. It is available as an 8- pin mini DIP-package.
Square wave generator using 555 IC
Astable multivibrator circuit can be use as a Square wave generator by changing certain changes as shown below.
Here In Astable multivibrator charging path for capacitor is through R1 and R2 , and discharging path through R2 and 7 (discharge ) pin. Because of two different path equation for Ton and Toff is different. So to generate square wave signal it must be same . So to do that I have connected diode parallel to R2 . Now charging path for capacitor is changed which is through R1 only . Now If we set the value of R1 and R2 equal then equation for Ton and Toff is same and we can get the square wave output as shown in the figure below.
Square wave generator using 555 IC
Astable multivibrator circuit can be use as a Square wave generator by changing certain changes as shown below.
Here In Astable multivibrator charging path for capacitor is through R1 and R2 , and discharging path through R2 and 7 (discharge ) pin. Because of two different path equation for Ton and Toff is different. So to generate square wave signal it must be same . So to do that I have connected diode parallel to R2 . Now charging path for capacitor is changed which is through R1 only . Now If we set the value of R1 and R2 equal then equation for Ton and Toff is same and we can get the square wave output as shown in the figure below.
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