Vaporizing circuit

[alexm1992]

Hi all, I have started a project but I need some advice. I have two cartridges with vaporizing coils . I want to ajust the current flow gradually from one coil to another. In other words I want 100% current to coil 1 and 0% current to coil 2, then when you turn a variable resistor to max you get 0% current to coil 1 and 100% current to coil 2. It is essential that the quantity of vaporized liquid remains constant regardless of resistance. Any ideas how this could be done, or any other ideas?

Cheers
Alex

 

[Harald Kapp]

You could use PWM to control the power to the coils with little losses in the control circuit. If you use one PWM signal for coil 1 and the inverse PWM signal for coil 2 you achieve the desired effect.

There are many ways to generate PWM signals. From a simple astable multivibrator based on two transistors, a circuit using a 555 timer IC or opamps to microcontroller based solutions.

In any case you will need a power stage to drive the presumeably high current through the coils.

 

[KrisBlueNZ]

It is essential that the quantity of vaporized liquid remains constant regardless of resistance.

Do you mean that the quantity of vapour from the first coil plus the quantity of vapour from the second coil must remain constant regardless of how much vapour is coming from each? If so, you need to know how the coil current relates to quantity of vapour.

Below a certain current, the coil temperature won't be high enough to generate any vapour at all. Above that current, the amount of vapour generated by a coil may not be proportional to the current (or the current with the vaporising threshold subtracted). You will need to find this out.

If the relationship is non-linear you may need to use a microcontroller to generate the current control signals (whether these are voltage signals or PWM signals) for the two coils, in response to a control signal.

If you want a more detailed response, you will have to provide a lot more details about your system. For example, the operating voltage and coil resistance would be a start.