Hello, This is my first post at this forum I hope you can help me out.
I am searching for a way how to design a circuit doing the following:
I have an electromotor of which I want to limit the rpm.
Attached is a dc power supply that, is soon as 12,3 volts are reached ( the faster the rotor spins the higher the voltage) has to deliver a power off signal.
With my limited knowledge of circuitry possibilities, a solution with a zenerdiode was the only option I could come up with that came close.
As soon as 12,3-12,5 volts are reached, the zenerdiode has to reach breakdown voltage.
This signal I then invert using a 7414 schmitt inverter and then I have my power off signal.
As the voltage drops below the 12,-3-12,5 volts, the zenerdiode blocks the current and the 7414 inverts it into an "on" signal.
The problem with zeners is that they have a tolerance and might not be that accurate.
How can I solve this? Or are there other, better possibilities to get a hard off at the required voltage?
I am searching for a way how to design a circuit doing the following:
I have an electromotor of which I want to limit the rpm.
Attached is a dc power supply that, is soon as 12,3 volts are reached ( the faster the rotor spins the higher the voltage) has to deliver a power off signal.
With my limited knowledge of circuitry possibilities, a solution with a zenerdiode was the only option I could come up with that came close.
As soon as 12,3-12,5 volts are reached, the zenerdiode has to reach breakdown voltage.
This signal I then invert using a 7414 schmitt inverter and then I have my power off signal.
As the voltage drops below the 12,-3-12,5 volts, the zenerdiode blocks the current and the 7414 inverts it into an "on" signal.
The problem with zeners is that they have a tolerance and might not be that accurate.
How can I solve this? Or are there other, better possibilities to get a hard off at the required voltage?