Panasonic KX-TG8421BX, Service Manual

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KX-TG8421BX/KX-TGA840BX
1.3. Block Diagram (Handset)
SPEAKER
RECEIVER
MIC
MIC
DET
SP
HEADSET
CHARGE CIRCUIT
Q4, Q9, R7Q4,
Q9,
R7
CHARGE CONTACTS
)
CHARGE(-)
CHARGE_CTRL
CHARGE
EEPROM
SCL
SDA
BATTERY TERMINAL
D7
VBAT
J1 J2
1.8 V
Q2Q2
1.8 V
LCD
CD
RESET
CSB SDA
SCL
CPU
Analog
Front
End
D/A A/D
33 35
15 16 19 20 18 28 32 31 57 58
36
13
43
42
63 54 55 66
ADPCM
Codec
Filter
DSP
Speech
Decoding
Speech
Encoding
BMC
Burst
Decoding
RF PA
IC801
Burst
Encoding
RF
PLL
MOD/DEMOD
5 3
4 3 6 7
8
9
2
77 78
75
RXn
RXon
ANT
DA801
RXp
TXp TXn Pon PSEL TXon
VDD-PADRY
9
10
XTAL
X1
10.368 MHz
BATTERY
44
ON SWITCH
KEYPAD
Charge
Pump
ROWS
COLUMNS
CP2.5V
CP4.0V
48, 49, 50, 51
22, 23, 24, 25, 26
BBIC
IC1
IC3
56
LCD-BACK LIGHT
KEY LED BELL LED
42 52 68
73 74 80
LDO_CTRL
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