How a mobile phone power on?

How a mobile phone power on?

Dear friends here we will discuss about what kind of functions a typical mobile phone has while powering on so let us start our new lesson. while starting i would like to say all of you that you please keep in touch with me by our contact us page and please don't feel any hesitation to ask me any question if you have about these lessons. these lessons will make you learn good repairing skills so keep reading these lectures.

First of all look at the picture below carefuly. this picture describe booting detail about nokia mobile phones but same structure can be applied to the other brands with a little modification.

In the picture above all of you can see a little block diagram illustrating mobile phone booting sequence. first of all I am starting explanation from power switch.

When apwer switch is pressed it turns on a ciruit inside the power IC and this IC starts distributing power suplly to other parts of mobile phones. On the first place VCO( voltage controlled ocsilator) or an other type of clock ocsilator starts producing a clock frequencey of 26MHz in some mobile phones this clock frequency is directly used to run CPU but most of the sets in nokia brands it is distributed bye hagar IC or RF Signal processor and it becomes 13MHz in the end of the division process. this low frequency cloack signal is used to start CPU functions now CPU which is like the brain of the mobile phone comes to the senses and first of all contacts its memory to know what are the instructions written it for this event and its memory tells CPU that if you feel that you are finding 13 MHz from hagar IC you have to run a booting test. in this test CPU tests most of the mobile phones function if they are correct CPU will order power IC to continue providing power to other parts and CPU also starts its display section. so this is the total process in which a mobile phone comes to the power on state.

Responsible parts for mobile phone power failure

there are eight elements which can affect mobile phone power on function

-Power Swicth

-Battery

-Battery terminal

-power supply tracks

-power IC

-Ocsilator (VCO)

-hagar IC

-flash (programming)

So we can say that when ever a mobile phone fails to power on there may be a fault in such type of parts which are used in mobile phone booting process