These are important parts if you are looking for shorts or opens on the DV series.
This image shows the location of the FDS6679. A common cause of shorts in the DV series.
When the power supply is plugged into the laptop and it shorts out/turns off it's usually caused by this MOSFET being shorted. Plainly stated. You plug the adapter into the DC Jack and the Blue Ring fails to light up, and the Power Supply shuts off. Giving no power to the tip. To reset adapter, unplug from AC (mains) and wait 15-30 sec. Then plug in again. The adapter is not damaged, since this is how it is protected.
These parts do not determine charge time or per centage.
The FDS6679 only closes to complete Positive circuit. The AO4407 only closes when the battery is plugged in. As a test- Check the voltage of the Drain side (pins 5-8) with AC adapter and no battery - you should see 0 volts. When you contect the battery you should have 10-14v depending on DV6000 or DV9000 series.
IF the AO4407 is open - The battery will not charge
IF the AO4407 is shorted - The unit will not come on
If the FDS6679 is open - the unit will not come on
If the FDS6679 is shorted - the AC Adapter will shut off/ No Ring light on laptop.
AO4407 when open, will not allow current/voltage to the battery charge section, so it will run off AC but not off the battery. This is the same for both DV6000, DV9000 and F700 series.
Chip: Alpha and Omega 4407 - http://www.aosmd.com/
FDS6679 - when shorted, unit will allow you to plug in AC adapter without shorting the adapter. The ring on the Power In shuts off, the Adapter shorts and will have to be unplugged (from laptop) before plugging it back into the wall power(mains). http://www.fairchildsemi.com/