Mikhail Naumov
VU Donator
Gold Contributor
Member For 3 Years
Member For 2 Years
ECF Refugee
Unlisted Vendor
Hi, i am looking to build my first pwm mod. I would like to know if the batteries are fully charged then drop to say 7v after a while of vaping, do you need to turn the pot up to get the same vape experience as when it was fully charged? Or does the voltage stay consistent until it is close to the depleted battery?
Yes. Unless it's very accurate RMS PWM with a 3-4S+ input, you'll notice drop offs in power at the same setting as your batteries die. PWM uses the maximum voltage of the cells constantly, it's just an unregulated box mod circuit made regulated. How? Well imagine you're the Flash and can press the firing button quicker than any human, that's what a 555 is doing in a PWM mod essentially with the pot an adjuster dial to tell it how much to pulse it. A PWM circuit is turning the power on and off at a set rate with the potentiometer setting being what tells it HOW OFTEN to pulse. At 100% on the pot, most mods simply will just fire directly. Like an unregulated box, as the 555 switches off and the board allows the maximum battery voltage to just pass through it.
So yes, in 2-3S PWM circuits that use a regular duty cycle, you will notice a drop off as the cells get lower. Just turn the pot up or use an input of 4S or higher to prevent this, as high voltage setups like a 4S can take a long time before you notice a drop in your power.