7
KX-TG8421HGN/KX-TGA840FXN
4 Technical Descriptions
4.1.
Block Diagram (Base Unit)
Analog
Front
End
To TEL_LINE
Bridge
Rect
D3 D3
Hook Switch
Q
4
,Q
5
Audio
Bell/Caller ID
Interface
CPU
18
16
23
20
21
19
24
BELL
HOOK
Off-Hook Line Voltage
25
A/D
D/A
ADPCM
Codec Filter
DSP
Speech Encoding
Speech Decoding
BMC
Burst Encoding
Burst Decoding
RF
PLL
5
3
77
75
9
10
EEPROM
SCL
SDA
57
58
44
To AC Adaptor
Limit
Resistor
Charge
Detector
CHARGE
CONTACT
(Optional)
VUNREG
3.0V
Reg.
IC
1
2.4V
Reg.
Q
9
1.8V
Reg.
Q
8
3.0 V
2.4 V
1.8 V
BBIC
IC401
IC7
KX-TG8421 BLOCK DIAGRAM
(BASE UNIT)
MOD/DEMOD
Charge
Pump
43
2.5V
XTAL
X
1
10.368
MHz
IC801
RX
n
RX
p
TX
p
TX
n
P
on
PSEL
V
DD
-PADRV
4
3
6
7
TX
on
RX
on
D801
6
72
ANT1
ANT2
9
8
ANT1
ANT2
RF PA
ANT1
ANT2
78
73
74
80
L1
L2
L1
L2
2
FLASH MEMORY
IC421
42
3.0V
54
55
56
53
TAM-CSN
SPI-DI
SPI-DO
SPICLK
Summary of Contents for KX-TGA840FXN
Page 2: ...2 KX TG8421HGN KX TGA840FXN ...
Page 14: ...14 KX TG8421HGN KX TGA840FXN 4 6 Signal Route ...
Page 15: ...15 KX TG8421HGN KX TGA840FXN ...
Page 21: ...21 KX TG8421HGN KX TGA840FXN 7 1 2 Answering System Settings 7 1 3 SMS Settings ...
Page 24: ...24 KX TG8421HGN KX TGA840FXN 7 6 Troubleshooting ...
Page 25: ...25 KX TG8421HGN KX TGA840FXN Cross Rreference For Service Hint P 28 ...
Page 26: ...26 KX TG8421HGN KX TGA840FXN ...
Page 27: ...27 KX TG8421HGN KX TGA840FXN ...
Page 28: ...28 KX TG8421HGN KX TGA840FXN 7 7 For Service Hint Cross Reference Battery Charge P 17 ...
Page 29: ...29 KX TG8421HGN KX TGA840FXN 8 Service Mode 8 1 Engineering Mode 8 1 1 Base Unit ...
Page 31: ...31 KX TG8421HGN KX TGA840FXN 8 1 2 Handset ...
Page 40: ...40 KX TG8421HGN KX TGA840FXN Cross Reference Check Point Base Unit P 48 ...
Page 42: ...42 KX TG8421HGN KX TGA840FXN Cross Reference Check Point Handset P 52 ...
Page 57: ...57 KX TG8421HGN KX TGA840FXN ...
Page 58: ...58 KX TG8421HGN KX TGA840FXN 10 1 2 Handset ...
Page 59: ...59 KX TG8421HGN KX TGA840FXN 10 1 3 Charger Unit ...
Page 60: ...60 KX TG8421HGN KX TGA840FXN 10 2 How to Replace the Handset LCD ...
Page 85: ...85 KX TG8421HGN KX TGA840FXN Memo ...
Page 97: ...97 KX TG8421HGN KX TGA840FXN 15 3 Cabinet and Electrical Parts Charger Unit ...
Page 98: ...98 KX TG8421HGN KX TGA840FXN 15 4 Accessories and Packing Materials 15 4 1 KX TG8421HGN ...
Page 99: ...99 KX TG8421HGN KX TGA840FXN 15 4 2 KX TGA840FXN ...