Panasonic KX-TG2248S Service Manual ▷ View online
15.1. Calling
15.2. To Terminate Communication
15.3. Ringing
15.4. Ports for Transmitting and
Receiving of Data
15 EXPLANATION OF BBIC (Base Band IC) DATA
COMMUNICATION
53
KX-TG2248S
16 BLOCK DIAGRAM (Base Unit)
Q150
IC332, Q102
IC100
IC331
Q151
Q50
Q7
D4
Q1
Q4
Q6
Q260
IC101
3.6V
IC201
MIP
LOUTO
KIN1
KIN2
KIN3
KIN4
KIN5
KIN6
KIN2
KIN3
KIN4
KIN5
KIN6
MIN
IC300
COM1~2
SEG3~12
LINO
SEG5
SEG6
SEG7
SEG8
SEG9
SEG10
SEG11
SEG12
COM1
COM2
SEG4
SEG3
STB5
STB4
STB3
STB2
STB1
NEW MSG_LED
VMOD
BMC CLOCK
8.192MHz
RSTH
CLK
DATA
LE
RXEN
TXEN
RX GAIN
SHCTRL
RSSI
RXDATA (RXI)
Key Scan
DTMF
LCD CON
Analog
SW
SW
LCD
Key matrex
BUF
3.3V
KX-TG2248S BLOCK DIAGRAM (BASE UNIT)
35
27
40
39
40
39
26
55
14
41
32
41
32
47
46
46
29
31
31
66
65
48
48
58
64
63
24
23
25
62
57
X200
82
83
84
85
86
87
56
3
74
95
61
99
59
60
18
19
20
21
22
52
51
26
LED903
LED902
LED900
79
69
36
34
2
SO
SI
CLK
CS
WP
RST
OPERATIONAL P.C.BOARD
RF_UNIT
DSP
ANSWER_LED
INSUE_LED
CHG_CTL
CHG
SPN
SPP
VCCPA
VCCA
VCC
POWER_DOWN
RESET
CIDIPO
CIDINO
BELL
DCINO
RLY
VRF
FLASH
MEMORY
VCC
SP
MIC
RESET
RECEIVE
AMP
AMP
SIDE_TONE
_CIRCUIT
_CIRCUIT
TR_RLY
INUSE
DETECT
BELL_
DETECT
DETECT
TEL_JACK
DC-
1
2
2
4
4
3
3
1
POWER DOWN
REGULATOR
REGULATOR
CHARGE
DETECT
DETECT
CHARGE
CONTROL
CONTROL
CHARGE_CONTACT
1
2
DC+
RING
TIP
KX-
TG224
8
S
54
General Description:
17 CIRCUIT OPERATION (Base Unit)
(DSP, Flash Memory) is a digital speakerphone/speech/signal processing system that implements all the functions of speech
compression, record and playback, and memory management required in a digital telephone answering machine.
compression, record and playback, and memory management required in a digital telephone answering machine.
The DSP system is fully controlled by a host processor DSP. The host processor provides activation and control of all that
functions as follows.
functions as follows.
17.1. DSP (Digital Speech/Signal Processing: IC201)
•
•
Voice Message Recording/Play back
The DSP system use a proprietary speech compression technique to record and store voice message in FLASH MEMORY.
An error correction algorithm is used to enable playback of these messages from the FLASH MEMORY.
•
•
DTMF Detection/Generator
The DTMF detection is implemented by the DSP system in software. The DTMF detection is performed during Record,
Playback, and Line Monitoring modes of operation.
Playback, and Line Monitoring modes of operation.
When the DTMF data from the Handset is received, the DTMF signal is output.
•
•
Synthesized Voice (Pre-recorded message)
The DSP implements synthesized Voice, utilizing the built in speech detector and an FLASH MEMORY, which stored the
vocabulary.
vocabulary.
•
•
Caller ID and Call Waiting CID demodulation
The DSP implements monitor and demodulate the FSK signals that provide CID information from the Central Office.
•
•
Analog Switching
The voice signal from telephone line is transmitted to the speaker or the voice signal from speakerphone microphone is
transmitted to the Telephone line, etc. They are determined by the signal path route operation of voice signal.
transmitted to the Telephone line, etc. They are determined by the signal path route operation of voice signal.
•
•
Block Interface Circuit
RF unit, LED, Key scan, Speaker, Microphone, Telephone line, LCD
17.2. Flash Memory (IC300)
Following information data is stored.
•
•
Voice signal
ex: Pre-recorded Greeting message, Incoming message
•
•
Telephone number, etc.
ex: Telephone Directory number, Caller ID data, ID code
•
•
Settings
ex: message numbers, caller ID numbers, pulse tone dial
55
KX-TG2248S
17.3. Power Supply Circuit
Function:
The power supply voltage from AC adaptor is converted to the desired voltage of each block.
Circuit Operation:
This unit supplies the voltage to each block as shown below.
17.3.1. Charge Circuit
The voltage from the AC is supplied to the main charge circuits. Normal charge (290 mA) of maximum 6-hours is started soon after
the Handset is placed on the base unit. Then it changes to trickle charge (15 mA on the average) to prevent from overcharging.
the Handset is placed on the base unit. Then it changes to trickle charge (15 mA on the average) to prevent from overcharging.
Normal charge : Q150 is ON
Trickle charge : Q150 is OFF
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KX-TG2248S
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