Error!UsetheHometabtoapply2tothetextthatyouwanttoappearhere.Error!Usethe
Hometabtoapply2tothetextthatyouwanttoappearhere. 1HardwareOverview
SatelliteL500DMaintenanceManual 1-15
1.4PowerSupply
Thepowersupplyunitprovidesconstantvoltage(19V)forthesystemboardandperformsthe
followingfunctions:
1.Powerinputmonitor
CheckswhethertheACadapter(DCpowersupply)isconnectedtothecomputer.
Checkswhetherthebatterypackisconnectedtothecomputer.
MonitorstheDCpowersupplyinputvoltage(ACAdapteroutputvoltage).
2.Powersupply'sinternalcontrol
Turnsonandoffthebatterypackchargingpowersupply.
Issuesachargingcurrentinstructiontothe PWMcontrolICofthebatt erypackcharging
powersupply.
ControlsthesupplyofDCpower supplyinput(ACAdapteroutpu t)tothepowersupply
unit.
Controlsthesupplyofpowertothesystemblock(load/logiccircuitside).
Controlsforcedshutdownifthepowersupplymalfunctions.
3.Logiccircuitcontrol
Instructsthegatearraytoenable/disabletuningthepoweron.
Controlspower-on/offoperation.
4.Statusdisplay
TurnsonthePowerLED(inGreen).
Batteryindicator(inGreenorAmber).
DC-INindicator(inGreen)
5.Externalinterface
PerformscommunicationthroughtheI2Cbus(viatheinternalEC/KBC).
Transfersthepowersupplyoperationmode.