How is the typical laptop's battery (multi-cell Li-Ion) and external power interfaced ? What all components go into designing that circuit ?
The required behavior is:
- When power cable is connected in DC Jack, the battery starts charging and the laptop starts running on the external power.
- When power cable is disconnected, laptop starts using batteries power.
- Stopping the battery to charge after is has been fully charged.
I know that DC jack has a third terminal which gets disconnected from ground the power cable is plugged in, I could imagine it's use in switching between battery and power supply but How should you charge the battery ?