Hi,
I want to create a PWM controller for a small DC motor (for academic reasons).
I figured that a 555 timer could create the appropriate pulse.
I simply got the 555 LED flasher (attached) and modified it slightly.
* Instead of the LED, I have the motor.
* R1 is 670Ω and R2 is 300Ω
* C2 is 0.1F
If I understnad it correctly, that should make a pulse frequency of about 15KHz at a ratio of about 1:1
I may have misunderstood it completely though.
Mostly is just makes a squealing noise, although sometimes it does turn.
The motor is just a small 9000RPM DC motor. It's a 6v motor, but I'm running it from a 9v battery (although it's only giving 7.7v). Would that be a problem?
Do I need a higher frequency pulse? Is there more to it than just creating a simple pulse that I would use to flash an LED?
Anyone know where I've gone wrong?
I want to create a PWM controller for a small DC motor (for academic reasons).
I figured that a 555 timer could create the appropriate pulse.
I simply got the 555 LED flasher (attached) and modified it slightly.
* Instead of the LED, I have the motor.
* R1 is 670Ω and R2 is 300Ω
* C2 is 0.1F
If I understnad it correctly, that should make a pulse frequency of about 15KHz at a ratio of about 1:1
I may have misunderstood it completely though.
Mostly is just makes a squealing noise, although sometimes it does turn.
The motor is just a small 9000RPM DC motor. It's a 6v motor, but I'm running it from a 9v battery (although it's only giving 7.7v). Would that be a problem?
Do I need a higher frequency pulse? Is there more to it than just creating a simple pulse that I would use to flash an LED?
Anyone know where I've gone wrong?
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