1.VALW / Power Always or main dc power supply
Power used in the circuit is usually dc consisting of 19V, 3.3. but there are also 15V – 20V adapter range voltage used depending on the laptop model.
It better to use Motherboard code ,by so doing we would know how much adapter voltage is recommended.Clevo motherboard manufacturer usually uses for 18.5V~3.2a Quanta 19V~3.4a Toshiba(15V-19V) , IBM(16V-19V) Compal-Inventec-Winstron- etc. ) .
VALW also supplys adapter current sensor detector usually supplied by charger IC (see datasheet to know how system charging/discharging works) ,When the charger ic sensor detects current adapter present ACIN~ACDET funcion pin on schema )and confirmed by SIO which manages charging system.
Acin / ACEDET is important as the voltage sensor for ic voltage charger enables it to pass (adp) Adapter fets current, which passes several resistor voltage of which 19V is scaled according to the demand of charger ic (V.i.R).
VALW /Always Voltage The main VALW supply comes from adaptor which originates from DC jack and flows to MAIN VALW Circuit.This is the MAIN POWER INSTALATION ON CIRCUIT, some uses FUSE (F) for safety some do not.This main power supply circuit using 1 or more P Channel mosfet transistor to maintain stabilized power and distribute power for Charger IC and DC/DC main power supply IC as VCC Power supply.This is an important power requirement to activate that component.
Make sure the voltage is present 19V_ALW for charger ic and Battery ic VCC and for adapter current sensor detector (greater than 2.4V). If this signal is missing, 19V supply will stop, being blocked by Analog ground coming from charging IC .Some other board blocking 19V by closing/opening gate P channel mosfet . Than 19V stop and won’t supply to +BAT line and deactivated motherboard 3V and 5V system.
DC / DC main power supply ic and upper /hi N channel (Source )need 19V adapter voltage as VCC power to activated component.
2.VS the Power Switch
VS is voltage that appears after switch on.The power button sends signal through EC_ON# (different board manufacture may have different pin name) to SIO otherwise known as v know by EMBEDDED CONTROLLER(EC) .EC starts to regulate signal by given signal gate to powere any device on VS state .
VALW main power suply standby to get N channel Sources when the signal ( open / close Gate ) transistor to pass voltage through Mosfet ( Drain ) as much as gate requirement than become Source for
VS voltage .The first one that must be understood is how the system works to enable/disable Power on VS
VS POWER SUPPLY for BOOTSTRAP DEVICE :There are three BOOTSTRAP device : Processor -Sodim -NB/SB/GPU chip ,each device has a different names of power :
PROCESSOR power name by VCCORE-CPUCORE,SODIM power name by VCCRAM,CHIP power name by VCCP .With out this power the device won’t display or not able to load boot up process .
VS for Boot Strap device
1.Procesor ( VCCORE ) Standard voltage 0.9 VS – 1.5VS
2.SODIM/RAM ( VCCRAM )
Standard Voltage rail for DDRII is 1.8VS and 0.9VTT and for DDRIII for 1.5VS and 0.75 VTT
3.CHIP POWER ( VCCP )
Check each chip datasheet to get Voltage rail to know their power
VS to Device
( Lcd / led , hdd , optical , usb , wifi , bloutooth , keyboard , sound , camera etc. ) For details on each Rail Voltage VS can be seen in the schema INDEX FOR EACH DEVICE.
3.Signal
( the wave triger / sensor /2 way confirmation signal / data interface)Signal function is open / close gate charge of organizing stages enable / disable each component or PCI ( Peripheral commucation interface ) .
System signal regulated by Microcontroller where the manufacturerhas made the format settings the form of firmware that is planted into the bios IC to managed embeddedcontrolling input output system for each ic interface.
Different circuit and component arrangement on the motherboard of course requiredifferent settings Microcontroller , so each different motherboard brand and series firmaware will necessarily require different settings .