Power Supply Circuit/Reset Circuit - Panasonic KX-TGC450G Service Manual

4.3.4 Power Supply Circuit/Reset Circuit
The power supply voltage from AC adaptor is converted to VBAT (3.0V) in IC302. And +3.0V for peripherals and analog part is
insulated from VBAT by Doubler of BBIC.
Circuit Operation:
5.5V
AC Adaptor
VDDC (1.2 V)
Reset (RSTN)
(IC501_54 pin)
Startmonitor
(IC501 57pin)
(CKM/STM)
VBAT
IC302
3.0V
RSTN(Reset)
REGULATOR
STM/CKM
VBAT
IC501
VBAT
pin 10
BBIC
pin 54
pin 57
pin 9
RF Part
ANS LED
MSG LED
BBIC chip initialize
- 14 -
+3.0V
pin 15
DOUBLER OUT
For peripherals
VDDC (1.2V)
IC601
FLASH
IC611
EEPROM
Q171
Receive
Amp.