sakai_tor wrote:I want the schematic of that chrger to fix it.please help me.Thank you
More than one charging power supply is used by iRobot in their series of robotic floor cleaners. I'll make a wild guess that yau are interested in the power supply, called the Fast Charger, that is used with most of the Discovery models. If that is a good guess, you should visit the Power Integrations web-site
and download a couple pdf files applicable to the TOPSwitch-GX series of switching power-supply controllers; their TOP245Y is used in the power supply. d/l their App-Note AN30, and d/l the Data Sheet.
Using the info in those documents, you will get an understanding of how the switcher functions. You will also see a basic schematic diagram for the power supply.
You can create your own schematic by reverse-ENGRG the Fast Chargers PWB assembly. You will find that the high-voltage section, shown in the PI dox, is used essentially unchanged in the Fast Charger; and you will see that the low-voltage section is fundamentally unchanged, except for addtion of the green, pilot LED, and some voltage regulation circuitry. At least that is my recollection.