DC to DC Regulators and Converters are packed in a tiny BGA (ball grid array) chips.
It used to convert, regulate and drives a certain amount of current-voltage.
It has the ability to stabilize, reduce or step up a voltage that feeds towards it.
in mobile phones it has a digital signal that been able to switch it on and off.
like for example it switch the LED lamp that used to light up the Display Screen while the cellphone is in used status and turn it off when the cellphone is not in use or at the sleep mode.
There are various kind and designed of these said components which according to each every purpose to the circuit. Sizes and bumps leads also have may differ with each other.
This chips may also damaged cause by a corrosive element or if a short circuit occurs.
