Panasonic KX-TD7895 - Digital Spread Spedtrum Telephone, Service Manual

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JT301 : ”High” Q309 : ON IC311(5) : “High“ IC311(3) : “High“ IC309(1) : “High“
IC307(7) : “High“
8.1.6. CHARGING DETECTION
If the Handset is put on the charger to recharge it, the DC voltage appears on "CHG+" terminal
of battery connector JT301.
PUT ON THE CHARGER Q309 ON IC307(34) CHARGE START
IC307(44) goes L Q312 ON Q311 ON JT300(CHG-CONT) L CHARGE STOP
9. CIRCUIT OPERATION (CHARGER)
IC602 amplifies the terminal voltages of R631 to R634 generated by the charge current about 10
times, then supplies them to IC601(5). IC601 controls the charge current and charges the 480mA
constant current so that the voltage of pin 5 becomes 1.25V. When charging is completed, the
CPU(307) of the portable unit sets the terminal of JT601 to "Low", then Q641 is turned ON.
Consequently IC601(3) exceeds 1.25V and switching of IC601 is suspended to stop charging.