I am working with the microcontroller MK22FN1M0AVMC12 and was reading about entering the low power modes and waking up from them.
I have provided two buttons connected to pins with LLUW functionality, so I can both go into low power modes using a combination of the pressed buttons, or a long-press of one of them, and also allow the wakeup using one of them as a LLUW interrupt.
My first question is if my approach is correct in this matter: Can I use only one button connected to a LLUW pin in order to both go in to sleep mode and wake up from it? This would function as the 'on_off' button of a device, when off means one of the deep sleep modes. Am I correct by doing this?
The second question I have is related to the 'internal regulator' mentioned in the different power modes. In my design I am not using the pins 'vregin' and 'vout33', mainly because I am already regulating a battery with an external regulator that also supplies other peripherals which need a higher current than the one provided by vout33. In this sense, I leave 'vregin' and 'vout33' floating, and use my regulated voltage as the input to the VDD pins. With this approach, am I affecting the functionality of the low-power modes since it controls the 'internal regulator'? or is the internal regulator a different one than the one used for vout33, and that is inside the uc after the VDD, in which case the approach of not using vout33 will still allow for the low power modes to work properly.
Besides this, is there any reason I should use the vout33 even if I already have a 3.3v regulated source?
Thank you in advance.