Panasonic KX-TG9120FXS User manual

© 2006 Panasonic Communications Co., Ltd. All
rights reserved. Unauthorized copying and
distribution is a violation of law.
ORDER NO. KM40610214CE
Telephone Equipment
KX-TG9120FXS
KX-TGA910FXS
Digital Cordless Answering System
Silver Version
(for Central Europe)

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KX-TG9120FXS/KX-TGA910FXS

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KX-TG9120FXS/KX-TGA910FXS
TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions----------------------------------------------- 4
1.1. For Service Technicians --------------------------------- 4
2 Warning -------------------------------------------------------------- 4
2.1. Battery Caution--------------------------------------------- 4
2.2. About Lead Free Solder (Pbf: Pb free)--------------- 4
3 Specifications ----------------------------------------------------- 6
4 Technical Descriptions ----------------------------------------- 7
4.1. Block Diagram (Base Unit) ------------------------------ 7
4.2. Circuit Operation (Base Unit)--------------------------- 8
4.3. Block Diagram (Handset)-------------------------------11
4.4. Circuit Operation (Handset)----------------------------12
4.5. Circuit Operation (Charger Unit) ----------------------13
4.6. Signal Route -----------------------------------------------14
5 Location of Controls and Components ------------------16
5.1. Controls -----------------------------------------------------16
6 Installation Instructions ---------------------------------------17
6.1. Connections------------------------------------------------17
6.2. Battery-------------------------------------------------------17
6.3. Expanding your phone system------------------------19
7 Operation Instructions-----------------------------------------20
7.1. Base Unit Settings----------------------------------------20
7.2. Handset Settings -----------------------------------------21
7.3. Registering a Handset to a Base Unit---------------22
7.4. Copying Phonebook Entries ---------------------------23
7.5. For Service Hint-------------------------------------------24
8 Service Mode -----------------------------------------------------25
8.1. Engineering Mode ----------------------------------------25
8.2. Copying Phonebook Items When Repairing-------30
8.3. How to Clear User Setting------------------------------32
9 Troubleshooting Guide ----------------------------------------33
9.1. Troubleshooting Flowchart -----------------------------33
9.2. Troubleshooting by Symptom (Base Unit and
Charger Unit) ----------------------------------------------41
9.3. Troubleshooting by Symptom (Handset) -----------45
9.4. How to Replace the Flat Package IC----------------49
9.5. How to Replace the LLP (Leadless Leadframe
Package) IC------------------------------------------------51
10 Disassembly and Assembly Instructions ---------------53
10.1. Disassembly Instructions -------------------------------53
10.2. Assembly Instructions -----------------------------------57
11 Measurements and Adjustments---------------------------58
11.1. The Setting Method of JIG (Base Unit) -------------58
11.2. Adjustment Standard (Base Unit)---------------------60
11.3. Adjustment Standard (Charger Unit)-----------------61
11.4. The Setting Method of JIG (Handset) ---------------62
11.5. Adjustment Standard (Handset) ----------------------64
11.6. Things to Do after Replacing IC ----------------------65
11.7. RF Specification-------------------------------------------66
11.8. How to Check the Handset Speaker or
Receiver ----------------------------------------------------67
11.9. Frequency Table (MHz) ---------------------------------67
12 Schematic Diagram ---------------------------------------------69
12.1. For Schematic Diagram---------------------------------69
12.2. Schematic Diagram (Base Unit_Main) --------------70
12.3. Schematic Diagram (Base Unit_Operation) -------72
12.4. Schematic Diagram (Handset) ------------------------74
12.5. Schematic Diagram (Charger Unit) ------------------76
13 Printed Circuit Board-------------------------------------------77
13.1. Circuit Board (Base Unit_Main) ---------------------- 77
13.2. Circuit Board (Base Unit_Operation)---------------- 79
13.3. Circuit Board (Handset) -------------------------------- 81
13.4. Circuit Board (Charger Unit)--------------------------- 83
14 Appendix Information of Schematic Diagram --------- 84
14.1. CPU Data (Base Unit) ---------------------------------- 84
14.2. CPU Data (Handset) ------------------------------------ 86
14.3. Terminal Guide of the ICs, Transistors and
Diodes ------------------------------------------------------ 89
15 Exploded View and Replacement Parts List ----------- 90
15.1. Cabinet and Electrical Parts (Base Unit)----------- 90
15.2. Cabinet and Electrical Parts (Handset)------------- 91
15.3. Cabinet and Electrical Parts (Charger Unit) ------- 92
15.4. Accessories and Packing Materials ----------------- 93
15.5. Replacement Parts List--------------------------------- 95

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KX-TG9120FXS/KX-TGA910FXS
1 Safety Precautions
1.1. For Service Technicians
ICs and LSIs are vulnerable to static electricity.
When repairing, the following precautions will help prevent recurring malfunctions.
1. Cover plastic parts boxes with aluminum foil.
2. Ground the soldering irons.
3. Use a conductive mat on worktable.
4. Do not grasp IC or LSI pins with bare fingers.
2Warning
2.1. Battery Caution
1. Danger of explosion if battery is incorrectly replaced.
2. Replace only with the same or equivalent type recommended by the manufacturer.
3. Dispose of used batteries according to the manufacturer's Instructions.
2.2. About Lead Free Solder (Pbf: Pb free)
Note:
In the information below, Pb, the symbol for lead in the periodic table of elements, will refer to standard solder or solder that con-
tains lead.
We will use PbF solder when discussing the lead free solder used in our manufacturing process which is made from Tin (Sn),
Silver (Ag), and Copper (Cu).
This model, and others like it, manufactured using lead free solder will have PbF stamped on the PCB. For service and repair
work we suggest using the same type of solder.
Caution
• PbF solder has a melting point that is 50°F ~ 70°F (30°C ~ 40°C) higher than Pb solder. Please use a soldering iron with temper-
ature control and adjust it to 700°F ± 20°F (370°C ± 10°C).
• Exercise care while using higher temperature soldering irons.:
Do not heat the PCB for too long time in order to prevent solder splash or damage to the PCB.
• PbF solder will tend to splash if it is heated much higher than its melting point, approximately 1100°F (600°C).
• When applying PbF solder to double layered boards, please check the component side for excess which may flow onto the
opposite side (See the figure below).

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KX-TG9120FXS/KX-TGA910FXS
2.2.1. Suggested PbF Solder
There are several types of PbF solder available commercially. While this product is manufactured using Tin, Silver, and Copper
(Sn+Ag+Cu), you can also use Tin and Copper (Sn+Cu), or Tin, Zinc, and Bismuth (Sn+Zn+Bi). Please check the manufac-
turer’s specific instructions for the melting points of their products and any precautions for using their product with other materi-
als.
The following lead free (PbF) solder wire sizes are recommended for service of this product: 0.3 mm, 0.6 mm and 1.0 mm.
2.2.2. How to Recognize that Pb Free Solder is Used
(Example: Handset P.C.B.)
(Flow Solder Side View)
Note:
The location of the “PbF” mark is subject to change without notice.
SOFT_C
SOFT_A
R59
C41
130
Q6
CN1
R136
C40
C49
C50
R134
R79
SW1
CLEAR
POWER_KEY
LED1
LED2
SP
1
2
36
5
7
0
#
R
4
9
8
INT
MIC
TALK
PbF
R58 R133
RA5
RA4 RA3 RA2
RA1
LED-K
LED-A
LED7
LED4LED6
LED3LED5
Marked

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KX-TG9120FXS/KX-TGA910FXS
3 Specifications

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KX-TG9120FXS/KX-TGA910FXS
4 Technical Descriptions
4.1. Block Diagram (Base Unit)
Analog
Front
End
To TEL_LINE
A B
CN1
Bridge
Rect D3
D3
Hook Switch
Q4,Q5 Audio
Bell/Caller ID
Interface
Analog
Switch
CPU
59 54
61
52 60 56 55
BELL
HOOK
Off-Hook Line Voltage 64 ADCO
D/A A/D
ADPCM
Codec Filter
DSP
Speech Decoding Speech Encoding
BMC
Burst Decoding
Burst Encoding
RF
Interface
18 19
TXDA
RXDA
15
21
20
22
RSSI SYCL SYDA SYEN
ANT1 ANT2
RF Module
18
16
2
31
8
21
14
13 12
12
13
XTAL
X1
10.368 MHz
EEPROM
SCL
SDA
6
5
To AC Adaptor
CN2
Limit
Resistor
CHARGE CONTACT
VUNREG
3.3V
Reg. IC1
2.5V
Reg. Q9
1.8V
Reg. Q8
3.3V 2.5V
1.8V
BBIC
IC5
FLASH
MEMORY
(TAM)
TAM Companion IC
RESET
CS
CS
10 11 12 13 14
SCK
SI SO
9
39 40 38 36 37 62
10 11 23 12
IC9
IC8
IC7
IC10
KX-TG9120 BLOCK DIAGRAM
(
BASE UNIT
)

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KX-TG9120FXS/KX-TGA910FXS
4.2. Circuit Operation (Base Unit)
4.2.1. Outline
Base Unit consists of the following ICs as shown in Block Diagram (Base Unit) (P.7).
• DECT BBIC (Base Band IC): IC7
- Handling all the audio, signal and data processing needed in a DECT base unit
- Controlling the DECT specific physical layer and radio section (Burst Module Controller section)
- ADPCM code filter for speech encoding and speech decoding (DSP section)
- Echo-cancellation and Echo-suppression (DSP section)
- Any tones (tone, sidetone, ringing tone, etc.) generation (DSP section)
- DTMF receiver (DSP section)
- Clock Generation for RF Module
- ADC, DAC, timer, and power control circuitry
- All interfaces (ex: RF module, EEPROM, LED, Analog Front End, etc.)
• RF Module: IC10
- PLL Oscillator
- Detector
- Compress/Expander
- First Mixer
- Amplifier for transmission and reception
• EEPROM: IC5
- Temporary operating parameters (for RF, etc.)
• FLASH MEMORY: IC9
- Voice Prompt (TAM) D/L Area
- ICM/OGM/MEMO Recording Area
• TAM Companion: IC8
- Voice data compression and decompression
- Speaker Amp
- LED Driver
• Additionally,
- Power Supply Circuit (+3.3V, +2.5V, +1.8V output)
- Crystal Circuit (10.368MHz)
- Charge Circuit
- Telephone Line Interface Circuit

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KX-TG9120FXS/KX-TGA910FXS
4.2.2. Power Supply Circuit
The power is supplied to the DECT BBIC, RF Module, EEPROM and Charge Contact from AC Adaptor (+6.5V) as shown in
Fig.101. The power supply is as follows;
• DECT BBIC (IC7):
CN2 (+6.5V) →IC1 →Q9 →IC7
CN2 (+6.5V) →IC1 →Q8 →IC7
• RF Module (IC10):
CN2 (+6.5V) →IC1 →Q9 →IC10 (PLL)
CN2 (+6.5V) →IC1 →Q10 →IC10 (Power AMP)
• EEPROM (IC5):
CN2 (+6.5V) →IC1 →Q9 →IC5
• FLASH MEMORY (IC9):
CN2 (+6.5V) →IC1 →IC9
• TAM Companion (IC8):
CN2 (+6.5V) →IC1 →Q9 →IC8
CN2 (+6.5V) →IC1 →Q8 →IC8
• Charge Contact (TP16):
CN2 (+6.5V) →R55, R56 →TP16
<Fig.101>

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KX-TG9120FXS/KX-TGA910FXS
4.2.3. Telephone Line Interface
<Function>
• Bell signal detection
• Clip signal detection
• ON/OFF hook circuit
Bell & Clip (: Calling Line Identification Presentation: Caller ID) signal detection:
In the standby mode, Q3 is open to cut the DC loop current and decrease the ring load.
When ring voltage appears at the L1T (A) and L1R (B) leads (when the telephone rings), the AC ring voltage is transferred as
follows;
•A→C4 →R6 →R33 →IC7 Pin 60 (CID INp)
•B→C3 →R4 →R35 →IC7 Pin 52 (CID INn)
ON/OFF hook circuit:
In the standby mode, Q3 is open, and connected as to cut the DC loop current and to cut the voice signal. The unit is conse-
quently in an on-hook condition.
When IC7 detects a ring signal or press the TALK Key onto the handset, Q4 turns on and then Q3 turns on, thus providing an
off-hook condition (DC current flows through the circuit) and the following signal flow makes the loop current.
•A→D3 →Q3 →Q5 →R21 →R22 →D3 →B [OFF HOOK]
4.2.4. Transmitter/Receiver
• Audio Circuits and DTMF tone signal circuits.
Base Unit and Handset mainly consist of RF Module and DECT BBIC.
Base Unit and Handset transmit/receive voice signal and data signal through the antenna on carrier frequency.
Signal Path:
*Refer to Signal Route (P.14).
4.2.4.1. Transmitter Block
The voice signal input from the TEL LINE interface goes to RF Module (IC10) through DECT BBIC (IC7) as shown in Block Dia-
gram (Base Unit) (P.7)
The voice signal passes through the analog part of IC7 where it is amplified and converted to a digital audio stream signal. The
burst switch controller processes this stream performing encryption and scrambling, adding the various other fields to produce
the GAP (Generic Access Profile) standard DECT frame, assigning to a time slot and channel etc.
In IC10, the carrier frequency is changing, and frequency modulated RF signal is generated and amplified, and radiated from
antenna. Handset detects the voice signal or data signal in the circuit same as the following explanation of Receiver Block.
4.2.4.2. Receiver Block
The signal of 1900 MHz band (1881.792 MHz ~ 1897.344 MHz) which is input from antenna is input to IC10 as shown in Block
Diagram (Base Unit) (P.7).
In IC10, the signal of 1900 MHz band is downconverted to 864 kHz signal and demodulated, and goes to IC7 as GAP (Generic
Access Profile) standard DECT frames. It passes through the decoding section burst switch controller where it separates out the
frame information and performs de-encryption and de-scrambling as required. It then goes to the DSP section where it is turned
back into analog audio. This is amplified by the analog front end, and goes to the TEL LINE Interface.
4.2.5. Pulse Dialling
During pulse dialing the hookswitch (Q3, Q4) is used to generate the pulses using the HOOK control signal, which is set high
during pulses. To force the line impedance low during the “pause” intervals between dial pulses, the PULSE_DIAL signal turns
on Q2.

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KX-TG9120FXS/KX-TGA910FXS
4.3. Block Diagram (Handset)
SPEAKER
RECEIVER
MIC
CN4
Headset
CHARGE
CIRCUIT
Q9,Q10,Q11
Q9,Q10,Q11
CHARGE
CONTACTS
CHARGE(+)
CHARGE(-)
CHARGE
CHARGE DETECT
SWITCHED
SUPPLY
Q1
Q1
BATTERY
BATTERY+
BATTERY-
TERMINAL
D10
VBAT1
DC/DC-SWITCH
3.0V
Q8
Q8
1.8V
Q7
Q7
4.0V 3.0V
1.8V
LCD
LCD_D/C
LCD_RESET
LCD_CS
WRITE
READ
WRITE
READ
CPU
Analog
Front
End
D/A
A/D
112
5
8
110
111
118
97
96
107
93
104
105
61
81
ADPCM
Codec
Filter
DSP
Speech
Decoding
Speech
Encoding
BMC
Burst
Decoding
Burst
Encoding
RF
Interface
RF
Module
IC20
26
28
RXDA
TXDA
25
38
39
40
RSSI
SYDA
SYEN
SYCL
20
21
XTAL
X1
X1
10.368
MHz
BATTERY
95
ON SWITCH
KEYPAD
ROWS
COLUMNS
57,58,62
50,51,52,53,54,80,83,84
BBIC
IC1
IC3
11
LCD-BACK LIGHT
KEY-BACK LIGHT
Ringer LED
SRAM_CS
Flash_CS
SRAM
79
42
44 43 59
13
60
1
2
3
4
5
KX-TGA910 BLOCK DIAGRAM (HANDSET)
SP AMP
IC6
_
DATA BUS
ADDRESS BUS
ADDRESS BUS: 3~9, 29~35, 122~128
DATA BUS: 68~75, 85~92
IC2
Flash ROM

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KX-TG9120FXS/KX-TGA910FXS
4.4. Circuit Operation (Handset)
4.4.1. Outline
Handset consists of the following ICs as shown in Block Diagram (Handset) (P.11).
• DECT BBIC (Base Band IC): IC1
- All data signals (forming/analyzing ACK or CMD signal)
- All interfaces (ex: Key, Detector Circuit, Charge, DC/DC Converter, Flash ROM, SRAM, LCD)
• FLASH MEMORY (substitute EEPROM): IC2
- Source program data and temporary user data are stored
•SRAM:IC3
- Application data and code are temporary stored
• RF Module: IC20
- PLL Oscillator
- Detector
- Compress/Expander
- Amplifier for transmission and reception
4.4.2. Power Supply Circuit/Reset Circuit
Circuit Operation:
When power on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6 V: BAT+) →F1, L1, D1 →Q7 (1.8 V), Q8 (3.0 V), Q1 (4.0 V)
The Reset signal generates IC1 (120 pin) and 1.8 V.
4.4.3. Charge Circuit
Circuit Operation:
When charging the handset on the Base Unit, the charge current is as follows;
DC+(6.5V) →R55, R56 →CHARGE+(Base) →CHARGE+(Handset) →Q10 →D10 →F1 →BAT+ ... Battery ...
BAT- →R43 →GND →CHARGE-(Handset)→CHARGE-(Base) →GND →DC-(GND)
In this way, the BBIC on Handset detects the fact that the battery is charged.
The charge current is controlled by switching Q10 of Handset.
Refer to Fig.101 in Power Supply Circuit (P.9).
4.4.4. Battery Low/Power Down Detector
Circuit Operation:
“Battery Low” and “Power Down” are detected by BBIC which check the voltage from battery.
The detected voltage is as follows;
• Battery Low
Battery voltage: V (Batt) 2.25V ± 50mV (When the back light disappeares)
The BBIC detects this level and “ ” starts flashing.
• Power Down
Battery voltage: V (Batt) 2.00V ~ 2.05V
The BBIC detects this level and power down.
4.4.5. Speakerphone
The hands-free loudspeaker at SP+ and SP- works as a ringer/alarm as well.

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KX-TG9120FXS/KX-TGA910FXS
4.5. Circuit Operation (Charger Unit)
4.5.1. Power Supply Circuit
The power supply is as shown.

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KX-TG9120FXS/KX-TGA910FXS
4.6. Signal Route

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KX-TG9120FXS/KX-TGA910FXS

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KX-TG9120FXS/KX-TGA910FXS
5 Location of Controls and Components
5.1. Controls
5.1.1. Base Unit
5.1.2. Handset

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KX-TG9120FXS/KX-TGA910FXS
6 Installation Instructions
6.1. Connections
Base unit
When connecting the AC adaptor to the base unit, a short
beep will be heard. If it is not heard, check the connections.
Charger
Connect the AC adaptor to the charger and route the cable
as shown. The charger can be mounted on the wall, if
required.
Note:
• Never install telephone wiring during a lightning storm.
• The AC adaptor must remain connected at all times. (It is
normal for the adaptor to feel warm during use.)
• The AC adaptor should be connected to a vertically oriented
or floor-mounted AC outlet. Do not connect the AC adaptor
to a ceiling-mounted AC outlet, as the weight of the adaptor
may cause it to become disconnected.
Location
• For maximum distance and noise-free operation, place your
base unit:
- away from electrical appliances such as TVs, radios, per-
sonal computers or other phones.
- in a convenient, high and central location.
6.2. Battery
6.2.1. Installation/Replacement
Important:
• Use only the included rechargeable batteries HHR-4EPT.
• When replacing batteries, we recommend using the Pana-
sonic rechargeable batteries P03P.
• Wipe the battery ends ( , ) with a dry cloth.
• When installing the batteries, avoid touching the battery
ends ( , ) or the unit contacts.

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KX-TG9120FXS/KX-TGA910FXS
6.2.2. Battery Charge
Note:
• It is normal for the handset to feel warm during charging.
• If you want to use the unit immediately, charge the batteries
for at least 15 minutes.
• Clean the charge contacts of the handset, base unit, and
charger with a soft, dry cloth, otherwise the batteries may
not charge properly. Clean if the unit is exposed to grease,
dust, or high humidity.
6.2.3. Battery Strength
6.2.4. Panasonic Ni-MH Battery Perfor-
mance (included batteries)
Note:
• It is normal for batteries not to reach full capacity at the initial
charge. Maximum battery performance is reached after a
few complete cycles of charge/discharge (use).
• Actual battery performance depends on a combination of
how often the handset is in use and how often it is not in use
(standby).
• Battery operating time may be shortened over time depend-
ing on usage conditions and ambient temperature.
• Even after the handset is fully charged, the handset can be
left on the base unit or charger without any ill effect on the
batteries.
• The battery strength may not be displayed correctly after you
replace the batteries. In this case, place the handset on the
base unit or charger and charge for at least 7 hours.

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KX-TG9120FXS/KX-TGA910FXS
6.3. Expanding your phone system

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KX-TG9120FXS/KX-TGA910FXS
7 Operation Instructions
7.1. Base Unit Settings
For your reference, a chart of all items which can be customised for the base unit is shown below.
• These items are customised using the handset.
• When customising the base unit, the current item or setting is highlighted on the display.
*1 Change the recall time, if necessary, depending on the requirements of your service provider/telephone company of PBX.
*2 The item will not be reset when pressing , , and keys of the handset. Refer to How to Clear User Setting (P.32).
*3 If you forget your PIN, see For Service Hint (P.24).
If you change the PIN, please make note of your new PIN. The unit will not reveal the PIN to you.
*4 The items are not shown on the display.
7.1.1. Answering System Settings
If the base unit is reset to its default settings, the following answering system-related settings will be reset.
7.1.2. SMS Settings
If the base unit is reset to its default settings, the following SMS-related settings will be reset. The contents of the receive and
send lists will be erased.