Circuit Operation (Charger Unit); Behavior Of Electric Power Failure - Panasonic KX-TG6611RUB Service Manual

4.5.

Circuit Operation (Charger Unit)

4.5.1. Power Supply Circuit
The power supply is as shown.
4.6.

Behavior of Electric Power Failure

BATT+
BATT_
In case that the power from AC adaptor is lost and lose radio waves, BBIC (IC1) turns IC6 ON since handset presumes that
base unit's power is failed.
Base unit detects that power voltage of AC adaptor +5.5V is OFF at IC351, then turns Q351 ON.
It's possible to use the units during the power failure, supplying power to VBAT of base unit from battery of handset through IC7,
CHG terminal and Q351.
F1
J1
AC Adaptor
Handset
IC7
VOUT
VIN
COUT
3
R45
BBIC
IC1
KX-TG6611RU/KX-TG6611UA/KX-TG6611CA/KX-TG6612CA/KX-TGA661RU
R1
CHG+
Q351
R354
D1
CHG-
R355
13
TP2
TP1
Base Unit
+5.5V
IC351
R351
VOUT
VIN
VSS
R352
VBAT