Panasonic KX-DT521RU Service Manual / Supplement ▷ View online
5
3. Headset Call
Transmitting signal is input from headset microphone
input to IC410-pin 26 amplified by a built-in analog amplifier of
IC410
A/D conversion, Gain adjustment and echo cancel by a built-in DSP of IC410.
Receiving signal is sent by data from PBX
Gain adjustment and D/A conversion by a built-in DSP of IC410 amplified by
a built-in analog amplifier of IC410
output from IC410-pin 42 output to headset speaker.
IC410
C571
R566
AGND
AGND
AGND
AGND
AGND
MICBIAS
L461
L462
R569
C576
C577
C578
C579
C581
R570
C580
DG
DCX81
26
LIN0
42
LOUT
CN400
2
CN205
13
3
HESMIN
HESSPOUT
12
Main PCB
IC205
ASIC2
Ope PCB
CN202
1
4
2
3
3
5
AGND
AG
C226
C205
AG EADGND
HEADGND HEADGND
HEADGND
HEADGND
R222
R223
C207
HEADGND
AG
HEADGND
C217
C218
D246
L209
D247
L210
L212
D245
L208
C221
6
GKEYIN0
6
Changed from Original Service Manual as section 8.
2 Troubleshooting Guide
2.1.
No Operation
Check the soldering.
Resolder or replace parts as needed.
Resolder or replace parts as needed.
Related parts: JK300,L301,L302,T300,D300,
C550,C551
NO
YES
Confirm the voltage between Pin + and Pin - of
C550.
Does it switch into 15V or 40V periodically?
C550.
Does it switch into 15V or 40V periodically?
Related parts: IC510,L309,D315,C550,C557,
C558,R541,R547
Connect DPT to PBX.
Remove L221(VDD33), L220(VCCA33) and
L222(VCC33) from Main PCB.
Disconnect Operation PCB from Main PCB.
L222(VCC33) from Main PCB.
Disconnect Operation PCB from Main PCB.
Related parts: D301,C306,R306-310,Q301,
C310,C311,R342,R343,C330,
Q331,D532,R348,R349,C333,
Q332,D533,R351-355,C335,
C336,IC300
Q331,D532,R348,R349,C333,
Q332,D533,R351-355,C335,
C336,IC300
NO
NO
Confirm the voltage between TP:3.3V and
TP:DG_A.
Does it switch into 0V or around 3.3V periodically?
TP:DG_A.
Does it switch into 0V or around 3.3V periodically?
YES
Remove DPT from PBX.
YES
Confirm the resistance value between "VDD33" and
TP:DG_A.
Is it about 367Ω ?
TP:DG_A.
Is it about 367Ω ?
Related parts:IC410,C420,C453,R427,
C421,C418,C419,C455
all parts around "MICBIAS"
NO
YES
Confirm the resistance value between "VCCA33"
and TP:DG_A.
Is it higher than 1MΩ ?
and TP:DG_A.
Is it higher than 1MΩ ?
Related parts:IC410,IC401,IC300,
LCD module,
all capacitors connected VCC33
all capacitors connected VCC33
NO
YES
Confirm the resistance value between "VCC33" and
TP:DG_A.
Is it higher than 1MΩ ?
TP:DG_A.
Is it higher than 1MΩ ?
Put L221(VDD33), L220(VCCA33) and
L222(VCC33) back in place.
Connect Operation PCB.
Connect DPT to PBX.
L222(VCC33) back in place.
Connect Operation PCB.
Connect DPT to PBX.
Related parts: [Main CPB ] CN400
[Ope PCB] CN205
NO
Confirm the voltage between TP:3.3V and
TP:DG_A.
Is it about 3.3V?
TP:DG_A.
Is it about 3.3V?
[ Power supply circuit ]
Confirm the resistance value between Pin1 and
Pin10 of CN205.
Is it higher than 1MΩ ?
Pin10 of CN205.
Is it higher than 1MΩ ?
Related parts:[Ope PCB]
YES
NO
YES
GO TO
A
D201,C202,
C204,IC205,C203,C201,
C211,C243,C213,C241
C204,IC205,C203,C201,
C211,C243,C213,C241
7
NO
YES
Check the TEST POINT(ST0-ST3).
See Table-1.
Is it "NOT Error (No.1)" ?
See Table-1.
Is it "NOT Error (No.1)" ?
YES
NO
YES
Confirm the LCD display.
Is it working?
Is it working?
END
Boot ROM Error into IC410 (No.2)
NO
Is it possible to call other telephone from DPT?
[ DCX81(IC410) ]
[ Flash ROM(IC401) ]
[ ASIC1(IC300) ]
A
[ LCD
]
[ ASIC2(
IC205
) ]
See Table-2 (
P.23
).
Flash ROM(IC401) Data Error
/ DSP Data Error (No.3,4,6,7)
See Table-3 (
P.24
).
ASIC2(IC205) Data Error (No.5)
See Table-4 (
P.25
).
See "
8.2
ASIC1(IC300) Does Not Operate".
See "
8.3
LCD Does Not Operate".
8
Table-1: PORT OUTPUT at ERROR
The error result is output to a port of IC410 at error. Check the Test Point ST3,ST2,ST1 and ST0.
See below for the output contents.
See below for the output contents.
Remarks: H=3.3V, L=0V
No.
Test Point
Error Item
Related Points
LCD Error Message.
ST3
ST2
ST1
ST0
1
H
H
H
L
NOT Error
2
H
H
H
H
No Power(+3.3V) Error
See Table-2
3
L
L
H
L
Flash ROM(IC401) Data Error
See Table-3
4
L
H
L
L
Flash ROM Data Error
See Table-3
5
H
L
H
L
ASIC(IC205) Data Ezzor
See Table-4
ERR 1001-0000
HARDWEAR ERROR
6
L
L
H
H
DSP Data Error
See Table-3
ERR 1003-0002
HARDWEAR ERROR
7
H
L
L
H
Flash ROM(IC401) Data Errorr
See Table-3
ERR 1003-1003
HARDWEAR ERROR
E
4
6
1
3
1
12
1 3
2 4
25
36
3 7
4 8
Q460
R 4 1 1
L 4 6 0
R415
L 4 6 1
L462
R418
R 4 1 9
R420
R421
R 4 2 2
R 4 2 4
R 4 2 8
C K 4 M
R S T N
R 4 3 8
R 4 3 9
C 4 0 2
R 4 4 0
3 . 3 V
C 4 1 3
R 4 5 3
C418
R454
C419
C 4 2 2
C427
R 4 6 3
C 4 2 8
C431
LCD_A0
H E S S P O U T
ST0
ST1
ST2
ST3
C 4 5 5
Q301
C 4 6 3
C 4 6 6
C467
PEP1
SPI_DO
4 . 5 V
ASIC_RST
G
R305
R 3 0 6
R307
R 3 0 8
ASIC_INT
LCD_RST
DG_A
R 3 3 0
R 3 3 1
R 3 3 2
R 3 3 3
R 3 3 4
C
C308
C 3 1 0
C 3 1 1
C 3 1 1
R 3 5 3
C323
C 3 2 6
C328
R 5 5 8
C 3 2 9
R559
R 5 6 3
C 3 3 5
R 5 6 6
R 5 6 9
1 . 2 V
R 5 7 0
H E S M I N
S C L
S D A
D 3 0 1
C 3 6 2
TP_LED+
TP_LED-
C563
C 5 6 4
C L 1
C 5 6 8
C 5 7 1
I C 3 0 0
C 5 7 6
C 5 7 7
C 5 7 8
L410
L 2 2 0
C 5 8 0
L 2 2 1
L 2 2 2
C582
PSYNC
C583
C585
C586
C 5 8 8
SPI_CS
SPI_CLK
D
E
MAIN BOARD BOTTOM VIEW
S T 0
S T 1
S T 2
S T 3
Click on the first or last page to see other KX-DT521RU service manuals if exist.