Panasonic KX-TG9385BXT User manual

© Panasonic Communications Co., Ltd. 2009.
Unauthorized copying and distribution is a violation
of law.
ORDER NO. KM40909013CE
Telephone Equipment
Model No. KX-TG9385BXT
KX-TGA939BXT
Digital Cordless Answering Systemstem
T: Titanium Black Version
(for Middle Near East and Africa)

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KX-TG9385BXT/KX-TGA939BXT

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KX-TG9385BXT/KX-TGA939BXT
TABLE OF CONTENTS
PAGE PAGE
1 Safety Precautions----------------------------------------------- 4
1.1. For Service Technicians --------------------------------- 4
2 Warning -------------------------------------------------------------- 4
2.1. About Lead Free Solder (Pbf: Pb free)--------------- 4
2.2. Discarding of P. C. Board-------------------------------- 5
3 Specifications ----------------------------------------------------- 6
4 Technical Descriptions ----------------------------------------- 7
4.1. Circuit Configuration of TG938x Series
Phones ------------------------------------------------------- 7
4.2. Block Diagram (Base Unit) ------------------------------ 8
4.3. Circuit Operation (Base Unit)--------------------------- 9
4.4. Block Diagram (Handset)-------------------------------12
4.5. Circuit Operation (Handset)----------------------------13
4.6. Circuit Operation (Charger Unit) ----------------------14
4.7. Signal Route -----------------------------------------------15
5 Location of Controls and Components ------------------18
6 Installation Instructions ---------------------------------------18
7 Operating Instructions-----------------------------------------18
8 Service Mode -----------------------------------------------------19
8.1. Engineering Mode ----------------------------------------19
8.2. Copying Phonebook Items when Repairing -------23
8.3. How to Clear User Setting------------------------------25
9 Troubleshooting Guide ----------------------------------------26
9.1. Troubleshooting Flowchart -----------------------------26
9.2. Troubleshooting by Symptom (Base Unit and
Charger Unit) ----------------------------------------------37
9.3. Troubleshooting by Symptom (Handset) -----------40
10 Disassembly and Assembly Instructions ---------------43
10.1. Disassembly Instructions -------------------------------43
10.2. Assembly Instructions -----------------------------------47
11 Measurements and Adjustments---------------------------50
11.1. Equipment Required -------------------------------------50
11.2. The Setting Method of JIG (Base Unit) -------------50
11.3. Adjustment Standard (Base Unit)---------------------53
11.4. Adjustment Standard (Charger Unit)-----------------54
11.5. The Setting Method of JIG (Handset) ---------------55
11.6. Adjustment Standard (Handset) ----------------------57
11.7. Things to Do after Replacing IC or X'tal ------------58
11.8. RF Specification-------------------------------------------60
11.9. How to Check the Handset Speaker or
Receiver ----------------------------------------------------61
11.10. Frequency Table (MHz) ---------------------------------61
12 Miscellaneous ----------------------------------------------------62
12.1. How to Replace the Flat Package IC----------------62
12.2. How to Replace the LLP (Leadless Leadframe
Package) IC------------------------------------------------64
12.3. Terminal Guide of the ICs, Transistors and
Diodes -------------------------------------------------------66
13 Schematic Diagram ---------------------------------------------67
13.1. For Schematic Diagram---------------------------------67
13.2. Schematic Diagram (Base Unit_Main) --------------68
13.3. Schematic Diagram (Base Unit_Operation) -------70
13.4. Schematic Diagram (Handset) ------------------------72
13.5. Schematic Diagram (Charger Unit) ------------------74
14 Printed Circuit Board-------------------------------------------75
14.1. Circuit Board (Base Unit_Main)-----------------------75
14.2. Circuit Board (Base Unit_Operation) ----------------77
14.3. Circuit Board (Handset) ---------------------------------79
14.4. Circuit Board (Charger Unit)--------------------------- 81
15 Exploded View and Replacement Parts List ----------- 82
15.1. Cabinet and Electrical Parts (Base Unit) ----------- 82
15.2. Cabinet and Electrical Parts (Handset)------------- 83
15.3. Cabinet and Electrical Parts (Charger Unit) ------- 84
15.4. Accessories------------------------------------------------ 85
15.5. Replacement Parts List--------------------------------- 86

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KX-TG9385BXT/KX-TGA939BXT
1 Safety Precautions
1.1. For Service Technicians
•Repair service shall be provided in accordance with repair technology information such as service manual so as to
prevent fires, injury or electric shock, which can be caused by improper repair work.
1. When repair services are provided, neither the products nor their parts or members shall be remodeled.
2. If a lead wire assembly is supplied as a repair part, the lead wire assembly shall be replaced.
3. FASTON terminals shall be plugged straight in and unplugged straight out.
•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
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 manufacture’s Instructions.
2.1. 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
contains 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
temperature 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-TG9385BXT/KX-TGA939BXT
2.1.1. 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
manufacturer’s specific instructions for the melting points of their products and any precautions for using their product with other
materials.
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. Discarding of P. C. Board
When discarding P. C. Board, delete all personal information such as telephone directory and caller list or scrap P. C. Board.

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KX-TG9385BXT/KX-TGA939BXT
3 Specifications
Note:
• Design and specifications are subject to change without notice.
Note for Service:
• Operation range: Up to 300 m outdoors, Up to 50 m indoors, depending on the condition.
• Analog telephone connection: Telephone Line

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KX-TG9385BXT/KX-TGA939BXT
4 Technical Descriptions
4.1. Circuit Configuration of TG938x Series Phones
TG938x consists of DECT cordless telephone.
Both voices of transmission and reception are transferred by PCM.
BBIC on DECT side controls the cordless telephone system.
DECT6.0
TGA939
Handset
PSTN DC
6.5V
RF unit
DECT6.0
BBIC
FLASH IC561
(Program)
EEPROM IC551
(Data)
TEL I/F POWER
Main PCB
Aidio signals
(PCM)
TAM
(IC701)
(IC501)
FLASH IC761
(Program)
MIC
SPEAKER

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KX-TG9385BXT/KX-TGA939BXT
4.2. Block Diagram (Base Unit)
LINE1
Q101
Transistor RLY
LINE2
T246
Transformer
Regurator 6.5V=>5V
FLASH
MEMORY
(Program)
EEPROM
RF UNIT
IC801
MIC SPEAKER
FLASH
MEMORY
(TAM)
Q102
Transistor RLY
5V
3.3V
5.0V
2.5V
Q231
Side Tone Circuit
D201
+ ~
- ~
Q201
Transistor RLY
T241
Transformer
IC261
BELL Detect/ Caller ID Circuit
3.3V
2.5V
3.0V 1.8V
D101
+ ~
- ~
IC701
TAM IC
3.0V
2.5V
3.0V
3.0V
5V
DC 6.5V
KEY/LED
LC DISPLAY
IC561 IC551
IC761
IC311
IC326 IC321
Q131
Side Tone Circuit
IC161
BELL Detect/ Caller ID Circuit
CHARGE CHG+
CHG-
L1 OUT
L1 IN L2 IN
L2 OUT
L1 CID L2 CID
L1 RLY L2 RLY
L1 BELL L2 BELL
KEY IN/OUT LED LCD I2C SPI BUS PCM
VDDIO
VDD
IC501
DSP IC
LDO 0 LDO 1
UART
CHG DET
RF I/F
PC102
PC202
KX-TG9385 BLOCK DIAGRAM (Base Unit_Main)

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KX-TG9385BXT/KX-TGA939BXT
4.3. Circuit Operation (Base Unit)
4.3.1. Outline
Base unit consists of the following ICs as shown in Block Diagram (Base Unit) (P.8).
• DECT BBIC (Base Band IC): IC501
- Handling all the audio, signal and data processing needed in a US DECT base unit
- Controlling the US 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: IC801
- PLL Oscillator
- Detector
- Compress/Expander
- First Mixer
- Amplifier for transmission and reception
• EEPROM: IC551
- Temporary operating parameters (for RF, etc.)
• FLASH MEMORY 1: IC761
- Voice Prompt (TAM) D/L Area
- ICM/OGM/Recording Area
• TAM Companion: IC701
- Voice data compression and decompression
- Speaker Amp
• Additionally,
- Power Supply Circuit (+5.0V, +3.3V, +3.0V, +2.5V, +1.8V output)
- Crystal Circuit (10.368 MHz)
- Charge Circuit
- Telephone Line Interface Circuit
• FLASH MEMORY 2: IC561
- Program DL
• LED Driver: IC641
• LCD Driver: IC641
• Key Matrix: IC631

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KX-TG9385BXT/KX-TGA939BXT
4.3.2. Power Supply Circuit
The power is supplied to the DECT BBIC, RF Module, EEPROM, TAM Companion, OP Amp, and Charge Contact from AC
Adaptor (+6.5 V) as shown in Fig.101. The power supply is as follows;
• DECT BBIC (IC501):
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q381 →IC501 (+3.0V)
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q386 →IC501 (+1.8V)
• RF Module (IC801):
DC Jack (+6.5 V) →F301 →D301 →IC311 →IC321 →IC801 (+2.5V output) (to Power AMP/PLL)
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q381 →IC801 (+3.0V)
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q386 →IC801 (+1.8V)
• EEPROM (IC551)/FLASH MEMORY 1 (IC561)/FLASH MEMORY 2 (IC761)/Latch (IC631/641)/OP Amp (IC171):
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q381 →(+3.0V)
• TAM Companion (IC701):
DC Jack (+6.5 V) →F301 →D301 →IC311 →IC326 →IC701 (+3.3V)
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q381 →IC701 (+3.0V)
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q386 →IC701 (+1.8V)
• OP Amp (IC161, IC261):
DC Jack (+6.5 V) →F301 →D301 →IC311 →D500 →Q386 →IC161/IC261(+1.8V)
• CHARGE
DC Jack (+6.5V) →F301 →D301 →R371, R372, R373, R374 →D362 →CHARGE+
<Fig.101>

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KX-TG9385BXT/KX-TGA939BXT
4.3.3. Telephone Line Interface
Note:
[ ]: Line 2
<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, Q101 [Q201] is open to cut the DC loop current and decrease the ring load.
When ring voltage appears at the L1T (A) [L2T (C)] and L1R (B) [L2R (D)] leads (when the telephone rings), the AC ring voltage
is transferred as follows;
ON/OFF hook circuit:
In the standby mode, Q101 [Q201] is open, and connected as to cut the DC loop current and to cut the voice signal. The unit is
consequently in an on-hook condition.
When IC501 detects a ring signal or press the TALK Key onto the cordless handset, Q103 [Q203] turns on and then Q101,
PC102, Q102 [Q201, PC202] turns on, thus providing an off-hook condition (DC current flows through the circuit) and the
following signal flow makes the loop current.
A [C] →D101 [D201] →Q101 [Q201] →Q131 [Q231] →R124 [R224] →R125 [R225] →Q102 [-] →D101 [D201] →B [D]
4.3.4. Transmit/Receive the signal
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 voice data of Signal Route (P.15).
Transmitter and receiver block of DECT RF describes as below.
4.3.4.1. Transmitter Block of DECT RF (For receiving of voice signal)
The voice signal input from the TEL LINE interface goes to RF Module (IC801) through DECT BBIC (IC501) as shown in Block
Diagram (Base Unit) (P.8)
The voice signal passes through the analog part of IC501 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 IC801, the carrier frequency is changing, and frequency modulated RF signal is generated and amplified, and radiated from
antenna. cordless handset detects the voice signal or data signal in the circuit same as the following explanation of Receiver
Block.
4.3.4.2. Receiver Block of DECT RF (For transmitting of voice signal)
The signal of 1900 MHz band (1920 MHz ~ 1930 MHz) which is input from antenna is input to IC801 as shown in Block
Diagram (Base Unit) (P.8).
In IC801, the signal of 1900 MHz band is downconverted to 864 kHz signal and demodulated, and goes to IC501 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.
4.3.5. Pulse Dialling
During pulse dialling the hookswitch (Q101, Q102, Q103, PC102/Q201, Q203, PC202) 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 (Q101, Q102/Q201).

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KX-TG9385BXT/KX-TGA939BXT
4.4. Block Diagram (Handset)
SPEAKER
RECEIVER
MIC
CHARGE CIRCUIT Q4, Q9, R7
Q4, Q9, R7
CHARGE CONTACTS
CHARGE(+) CHARGE(-)
CHARGE HANDSET-DET
CHARGE DETECT
EEPROM SCL
SDA
BATTERY TERMINAL
D7
VBAT
J1
J2
1.8 V
Q2
1.8 V
LCD
CD
RESET
CSB SDA
SCL
CPU
Analog
Front
End
D/A A/D
33 35
15 16
19 20 18 20
31 32 57 58
WP 53
36 40
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
ANT1 ANT2
5 3
4 3 6 78
9
6
2
77 78
75
RXn
RXon
D802
ANT1
D801
RXp
TXp TXn Pon PSEL TXoh
VDD-PADRY
9
10
XTAL
X1
10.368 MHz
BATTERY
44
TALK OFF
KEYPAD
Charge
Pump
ROWS
COLUMNS
CP2.5V CP4.0V
27, 49, 50, 51
22, 23, 24, 25, 26
BBIC
IC1
IC3
56
LCD-BACK LIGHT
KEY LED BELL LED
65 52 68
KX-TGA939 BLOCK DIAGRAM (Handset)
73 74 80
72
ANT2
ANT2
1 2 3 4 5

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KX-TG9385BXT/KX-TGA939BXT
4.5. Circuit Operation (Handset)
4.5.1. Outline
Handset consists of the following ICs as shown in Block Diagram (Handset) (P.12).
• 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, EEPROM, LCD, RF Power Amp.)
- PLL Oscillator
- Detector
- Compress/Expander
- Reception
• RF Power Amp: IC801
- Amplifier for transmission
• EEPROM: IC3
- Temporary operating parameters (for RF, etc.)
4.5.2. Power Supply Circuit/Reset Circuit
Circuit Operation:
When power on the Handset, the voltage is as follows;
BATTERY(2.2 V ~ 2.6 V: BATT+) →F1 →Q2 (1.8 V), IC1-43pin (2.5V)
The Reset signal generates IC1 (61 pin) and 1.8 V.
4.5.3. Charge Circuit
Circuit Operation:
When charging the handset on the Base Unit, the charge current is as follows;
DC+(6.5 V) →F301 →D301 →R371, R372, R373, R374 →D362 →L361 →L362 →CHARGE+(Base) →CHARGE+
(Handset) →L4 →Q4 →D7 →F1→BATTERY+... Battery...
BATTERY- →R45 →GND →L5 →CHARGE-(Handset) →CHARGE-(Base)→L371 →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 Q4 of Handset.
Refer to Fig.101 in Power Supply Circuit (P.10).
4.5.4. 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) 2.25 V ± 50 mV
The BBIC detects this level and " " starts flashing.
• Power Down
Battery voltage: V(Batt) 2.0 V ± 50 mV
The BBIC detects this level and power down.
4.5.5. Speakerphone
The hands-free loudspeaker at SP+ and SP- is used to generate the ring alarm.

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KX-TG9385BXT/KX-TGA939BXT
4.6. Circuit Operation (Charger Unit)
4.6.1. Power Supply Circuit
The power supply is as shown.

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KX-TG9385BXT/KX-TGA939BXT
4.7. Signal Route

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KX-TG9385BXT/KX-TGA939BXT

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KX-TG9385BXT/KX-TGA939BXT

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KX-TG9385BXT/KX-TGA939BXT
5 Location of Controls and Components
Refer to the Operating Instructions.
Note:
You can download and refer to the Operating Instructions (Instruction book) on TSN Server.
6 Installation Instructions
Refer to the Operating Instructions.
Note:
You can download and refer to the Operating Instructions (Instruction book) on TSN Server.
7 Operating Instructions
Refer to the Operating Instructions.
Note:
You can download and refer to the Operating Instructions (Instruction book) on TSN Server.

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KX-TG9385BXT/KX-TGA939BXT
8 Service Mode
8.1. Engineering Mode
8.1.1. Base Unit

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KX-TG9385BXT/KX-TGA939BXT
Frequently Used Items (Base Unit)
ex.)
Note:
(*1) When you enter the address or New Data, please refer to the table below.
(*2)
Items Address(*1) Default Data New Data Remarks
C-ID (FSK) sensitivity 03 53 00 01 (6 dB up) 02 (12 dB up) When hex changes from “00” to “01” or “02”, gain
increases by 6 dB or 12 dB.
C-ID (DTMF) sensitivity 03 61 50 60 (6 dB up) 70 (12 dB up) When hex changes from “50” to “60” or “70”, gain
increases by 6 dB or 12 dB.
Frequency 00 01 60 - - Use these items in a READ-ONLY mode to confirm
the contents. Careless rewriting may cause serious
damage to the computer system.
ID 00 10~00 14 Given value - -
Bell length 02 11 64 (10 sec) (*2) 1E (3 sec) 14 (2 sec) This is time until bell stops ringing.
(Unit: 100 ms)
PULSE Dial speed
(10PPS -> 20PPS)
02 4D 28 (40 msec) (*2) 14 (20 msec) - This is pulse make time. (Unit:1 ms)
02 4E 3C (60 msec) (*2) 1E (30 msec) - This is pulse break time. (Unit:1 ms)
01 FB 58 (870 msec)
(*2)
2D (440 msec) - This is inter-digit time in pulse mode.
(Unit:10 ms)
Desired Number (hex.) Input Keys Desired Number (hex.) Input Keys
00 A[FLASH]+0
11 B[FLASH]+1
.. C[FLASH]+2
.. D[FLASH]+3
.. E[FLASH]+4
99 F[FLASH]+5
Bell length 64(hex) = 100(dec) →100 ×100 msec = 10000 msec (10 sec)
PULSE Dial speed
(10PPS -> 20PPS)
28 (hex) = 40 (dec) →40 ×1 msec = 40 msec
3C (hex) = 60 (dec) →60 ×1 msec = 60 msec
58 (hex) = 88 (dec) →(88 - 1) ×10 msec = 870 msec