Panasonic KX-TS550MEB User manual

© 2007 Panasonic Communications Co., Ltd. All
rights reserved. Unauthorized copying and
distribution is a violation of law.
KX-TS550MEB
KX-TS550MEW
Integrated Telephone System
Black Version
White Version
(for Mexico)
Telephone Equipment
ORDER NO. KM40706334CE

1 ABOUT LEAD FREE SOLDER (PbF: Pb free) 3
1.1. Suggested PbF Solder 3
2 FOR SERVICE TECHNICIANS 4
3 CAUTION 4
4 LOCATION OF CONTROLS 5
5 SETTINGS 6
5.1. Connection 6
6 OPERATIONS 7
6.1. Making Calls 7
6.2. Answering Calls 7
7 SPECIAL FEATURES 7
7.1. For Call Waiting Service Users 7
7.2. Temporary Tone Dialing (For Rotary or Pulse Service
Users) 7
8 DISASSEMBLY INSTRUCTIONS 8
9 TROUBLE SHOOTING GUIDE 9
9.1. Service Hints 9
9.2. Pulse Dialing Problems 9
9.3. Problems With the Handset 10
9.4. Tone Dialing Problems 10
9.5. Problems With Ringer 11
9.6. How to Check the IC1 (Scanning to the key) 12
10 BLOCK DIAGRAM 13
11 OPTION JUMPER TABLE 14
12 CIRCUIT OPERATIONS 15
12.1. Telephone Line Interface and Pulse Dial Circuit 15
12.2. Tone Dial Circuit 15
12.3. Power Circuit and Redial Back-up Circuit 17
13 CPU DATA 18
14 CABINET AND ELECTRICAL PARTS LOCATION 20
15 ACCESSORY AND PACKING MATERIALS 21
16 TERMINAL GUIDE OF ICs TRANSISTORS AND DIODES 22
17 REPLACEMENT PARTS LIST 23
17.1. Base Unit 23
17.2. Accessories And Packing Materials 24
17.3. Screw 24
18 FOR SCHEMATIC DIAGRAM 25
19 SCHEMATIC DIAGRAM 26
19.1. Memo 28
20 CIRCUIT BOARD 29
20.1. Main (Component View) 29
20.2. Main (Flow Solder Side View) 30
20.3. Operation (Flow Solder Side View) 31
Note for TABLE OF CONTENTS:
Because sections 5, 6 and 7 of this manual are extracts from the operating instructions for this model, they are subject to change
without notice. You can download and refer to the original operating instructions on TSN Server for further information.
CONTENTS
Page Page
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KX-TS550MEB / KX-TS550MEW

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).
1 ABOUT LEAD FREE SOLDER (PbF: Pb free)
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 manufac
turer’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: 0.3mm, 0.6mm and 1.0mm.
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KX-TS550MEB / KX-TS550MEW

2 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 unit 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.
3 CAUTION
Danger of explosion if battery is incorrectly replaced. Replace only with the same or equivalent type recommendenced by the
manufacturer.
Dispose of used batteries according to the manufacture’s Instructions.
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KX-TS550MEB / KX-TS550MEW

4 LOCATION OF CONTROLS
5
KX-TS550MEB / KX-TS550MEW

5 SETTINGS
5.1. Connection
6
KX-TS550MEB / KX-TS550MEW

6 OPERATIONS
6.1. Making Calls
6.2. Answering Calls
7 SPECIAL FEATURES
7.1. For Call Waiting Service Users
7.2. Temporary Tone Dialing (For Rotary or Pulse Service Users)
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KX-TS550MEB / KX-TS550MEW

8 DISASSEMBLY INSTRUCTIONS
Shown in Fig —. To remove —. Remove —.
1Lower Cabinet Screws(2.6×10).............(A)×5
2P.C. Boards Remove the P.C.Boards
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KX-TS550MEB / KX-TS550MEW

9 TROUBLE SHOOTING GUIDE
9.1. Service Hints
SYMPTOM CURE
No Tone Dialing Check IC1, Q2, Q1, C22 and VR1.
Dead Check IC1, Q2, Q1 and D17.
Rings, no dial tone, no pulse or tone dial Check Q1, Q2, Q7, D17 and Q3.
No rings Check C1, R2 and IC2.
No volume Handset Check IC1, VR1, C15 and C22.
Buttons stick under upper cabinet assembly. From key board Adijust the setting of buttons.
No pulse dial Check Q1, Q2 and IC1.
9.2. Pulse Dialing Problems
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KX-TS550MEB / KX-TS550MEW

9.3. Problems With the Handset
9.4. Tone Dialing Problems
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KX-TS550MEB / KX-TS550MEW

9.5. Problems With Ringer
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9.6. How to Check the IC1 (Scanning to the key)
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KX-TS550MEB / KX-TS550MEW

10 BLOCK DIAGRAM
MELODY
SEQUENCER
LINE ADAPTATION
POWER EXTRACTION
DC MASK
CONTROL
LOGIC
TONE
GENERATOR
RING
FREQUENCY
DISCRIMINATION
OSC
RAM
MUTE
DIALLER
LINE
CURRENT
SENSE
SOFT CLIP
AGC
V
DD
LI CI LS RI STB A
GND
LED
V
DD
V
SS
MO FCI
HS/DP LLC OSC MFL MODE C1 C2 C3 C4
R1 R2 R3 R4
M2 M1
RO
CS
IC1
KEY PAD
R9
sv1
AGND
3.58 ADL
RS
R
T
Q1
Q2
D23
R55
R103
S3
L H OFF
D24
R14
IC2
R2
C1
Q8
Q3
Ringer
D2 C34
D17
C22
HS Speaker
HS MIC
R10 C5
C9
R5 R6
KX-TS550 BLOCK DIAGRAM
R102
58
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KX-TS550MEB / KX-TS550MEW
13

11 OPTION JUMPER TABLE
Note:
Refer to Main (Flow Solder Side View) (P.30)
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KX-TS550MEB / KX-TS550MEW

12 CIRCUIT OPERATIONS
12.1. Telephone Line Interface and Pulse Dial Circuit
When the hook switch SW1 is ON (off-hook), the circuit is closed, and current is supplied to the base of Q2 via the diode bridge
D17 and Q2 is On →Q1 is ON (OFF-HOOK condition).
Q1 and Q2 are the dial pulse generating circuits, and are driven by the DIALER (IC1), when the DIALER Pin 10 of IC1 is LOW →
Q2 is OFF and Q1 is OFF (break). If port Pin 10 is HIGH →Q2 is ON →Q1 is ON (make).
12.2. Tone Dial Circuit
Function:
The tone dialing circuit consists of a DTMF (Dual Tone Multi Frequency) signal generator (outputted from Pin 25 of the IC1) for
tone dialing, and also a circuit for outputting the signal to line.
The DTMF circuit identifies inputs from the 12 keys (1,2,3,4,5,6,7,8,9,0, and #) by means of a total of seven frequencies, that
is four low frequencies (Low group) and three high frequencies (High group).
Circuit Description:
When a dial key is pressed, a DTMF signal is output from Pin 25 of IC1 as an analog synthetic wave.
The signal flow to the line is as follows.
Pin 25 of IC1 →Q3 →R9 →Q1 →Tel Line.
The DTMF signal is sent to the line via the following path. Q3 is an amplifier which is used to output the signal to line.
Shown below is the signal flow used to output the DTMF signal from the handset as a monitor tone when a dial key is pressed.
Pin 3 of IC1 →VR1 →C15 →Handset Speaker.
The signal combination and frequency corresponding to each dial key is shown on next page.
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KX-TS550MEB / KX-TS550MEW

12.3. Power Circuit and Redial Back-up Circuit
Function:
This set is powered from the line. When it is an OFF-HOOK status, Tel Line →D17 →Q1 →R9 →Pin 27 of IC1 (to become
the power supply for IC1 speech network).
The voltage from the line is turned into a constant voltage by D2 and then supplied to the IC1, reset circuit.
Through Tel Line →R1 →R3 →D17 →R14 to become the power supply for IC1, and the redial Back-up will be done.
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KX-TS550MEB / KX-TS550MEW

13 CPU DATA
IC
Clock frequency: 3.58MHz
Operating range: 13~100mA
Pin
No. Symbol Function Pin
No.
15
16
17
18
19
20
21
22
23
24
25
26
27
28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LS
MFL
RO
V
DD
A GND
STB
CI
MO
LLC
HS/DP
OSC
MODE
C4
C3
Line Current Sense Input
MF Level Setting
Receive Output
Positive Voltage Supply
Analogue Ground
Side Tone Balance Input
Complex Impedance Pin
Melody Output
Line Loss Compensation
Hook Switch Input and Dial Pulse Output
Oscillator Input
Signalling Mode Select Input
Keyboard Column
Keyboard Column
Symbol Function
C2
C1
R4
R3
R2
R1
FCI
LED
M1
M2
CS
V
SS
V SS
LI
RI
Keyboard Column
Keyboard Column
Keyboard Row
Keyboard Row
Keyboard Row
Keyboard Row
Frequency Comparator Input
LED Output Driver
Microphone Input
Microphone Input
Current Shunt Control Output
Negative Power Supply
Line Input
EMC ground connection
Receive Input
V
SS
1VSS 28
LS 1
MFL 2
RO 3
V
DD 4
A
GND 5
STB 6
CI 7
MO 8
LLC 9
V
SS V SS
HS/DP 10
OSC 11
MODE 12
C4 13
C3 14
C2 15
C1 16
R4 17
R3 18
R2 19
R1 20
FCI 21
LED 22
M1 23
M2 24
CS 25
V
SS 26
LI 27
RI 28
U4
U5
C1
C2 C3 C5 C4 C6
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KX-TS550MEB / KX-TS550MEW

14 CABINET AND ELECTRICAL PARTS LOCATION
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KX-TS550MEB / KX-TS550MEW