Anyone help me to calculate the frequency of LM324 circuit

[lick_man]

lm324 circuit

This circuit here:

On pin 1 there is a square wave
on pin 10 there is a sawtooth wave
they are the same frequency. But I can't calculate.
I need a help.

 

[IanP]

lm324 circuits

Use this simplified formula for triangle/square wave generator based on 2 opamps:

f=1/ (2 *R*C)
(see example at: https://www.electronics-lab.com/projects/test/010/ )
In your case R=R3, C=C1 .. and f≈270Hz

Regards,
IanP

 

[lick_man]

lm324n wave generator

thanks IanP
but could you tell me how to have this fomula?
by expression.
Thanks so much

 

[IanP]

lm324n circuits

This formula applies only for rough estimation and is valid with certain assumptions ..
If you, however, need exact equations goto this site:
http://www.ecircuitcenter.com/Circuits/op_tri_gen/op_tri_gen.htm

Regards,
IanP

 

[contagiouseddie]

lm324

IanP

May I know what is the function of this circuit. I have used LM324 in my circuits before but never came across this circuit configuration.

Thanks you in advance.

 

[IanP]

lm324 pwm circuits

U1A + U1B --> triangle wave generator ..
Output of U1C (comparator) is PWM (pulse width modulated) wave; in this case it is speed controller of a fan ..

Regards,
IanP