Do all regulated mods use some form of PWM?

[conanthewarrior]

Hi everyone, I hope you are all OK.

I was just using my IPV8 with a SS316L build, and for the first time noticed the tell tale noise of PWM. It was only because I fired ear my ear for some reason.

I really should of asked this question a long time ago, and am fairly sure they do use PWM in most cases, some boards at much higher rates than others resulting in a smoother vape, but I just wanted to be certain, as I know the Evolv boards are marketed as DC-DC convertors so I wondered if it was a flat signal.

So, do all regulated mods use PWM to achieve your set wattage?

Also, for TC I notice with my Evolv powered devices the wattage drop on screen when you hit your set temperature. With my other mods, for example ones that use Yihi boards, this does not show.
So does wattage decrease with the Yihi boards like the DNA, or does it pulse at a slower rate achieving a similar effect to reducing wattage?

Thanks for everyone that takes the time to help me out, Conan.

 

[Wingsfan0310]

Evolv uses DC-DC. Yihi's higher end mods use DC-DC for power mode but PFM in TC. I'm not sure what there lower end boards use.

Cheers,
Steve

Edit Check out the end of the video, it's around the 59 minute mark

 

[VapeNMirrors]

Yes, Evolv boards will reduce voltage in TC mode once temp is hit while Yihi boards will always fire the coil with the same energy (Joules) and do so with PFM to regulate temp. Watts is energy over time so they both regulate wattage to maintain temp.

 

[conanthewarrior]

Thank you both for your answers, they was helpful and the video was fantastic too.

I'm glad I am 100% on that matter now. Looking at the graphs in the video, I must not be that good at detecting the PFM Yihi uses, as I enjoy both my Evolv mods and Yihi for temperature control.
I can notice bad TC though, for example my Xcube 2 you can feel the temperature fluctuating when using SS. With Yihi and Evolv I do not notice this so enjoy mods that use boards by either manufacturer for TC.