Technical Support POWER SWITH LOGIC

[pankajbiyani]

HOW TO WORK POWER SWITH LOGIC IN LAPTOP FULL EXAPLAIN

 

[Ahmad Safari]

First, when the charger is connected, the voltage enters the charging circuit.
In some models, such as HP, the adapter communicates with the IC and if the adapter is approved, the charging circuit is activated.


The voltage enters the charging circuit, two MOSFETs act as protective switches.
If the voltage is normal, these MOSFETs will turn on and the voltage will enter the motherboard.
We call this voltage B+.

The rest of the system voltages are generated from B+ voltage.
At first, 3 V LDO voltage is produced.
This voltage is for EC.


After the EC starts working, the command to generate the voltages is given. This point is a little different in some models.
Usually, ALW voltage includes 3 and 5 volts.
After the voltage is set, the system waits for the switch button to be pressed.
By pressing the switch button, the activator signal is transferred between EC and PCH, and you should check it from the power rail in the schematic.
Finally, the voltages of the switch stage are made.