Sharp LL-171ME Service Manual ▷ View online
LL-171ME
TROUBLESHOOTING
4 – 3
(Yes)
(Yes)
(Yes)
(No)
Sound signals are input to
MSP3415 (UT10) (Pins 41, 42 in
external input)?
MSP3415 (UT10) (Pins 41, 42 in
external input)?
Check each sound signal
line and AV connector and
cable.
line and AV connector and
cable.
(No)
5-V voltage is input to Pins 10,
49, 63 of MSP3415 (UT10) and
9-V voltage to Pin 31.
49, 63 of MSP3415 (UT10) and
9-V voltage to Pin 31.
Check U12 and circuits
around it.
around it.
(No)
IIC bus (Pins 1, 2 of UT10) is
normal?
normal?
TV tuner (UT13)
VPC3230 (UT8)
PW1231 (U29)
PW166 (U21)
THC63LVDM83A (U24)
Connector (W5)
LCD relay PWB connection cable
LCD relay PWB
LCD unit
VPC3230 (UT8)
PW1231 (U29)
PW166 (U21)
THC63LVDM83A (U24)
Connector (W5)
LCD relay PWB connection cable
LCD relay PWB
LCD unit
AD9883A (U19)
PW166 (U21)
THC63LVDM83A (U24)
Connector (W5)
LCD relay PWB connection cable
LCD relay PWB
LCD unit
Input to speaker?
Check IIC bus line and
around it.
around it.
(Yes)
(No)
Sound is heard when AV or PC
sound is input.
sound is input.
(Yes)
(Yes)
The TV signal is nomal reception?
(Yes)
Pins 36 of UT5 (R129) and 37
(R128) have a synchronous input?
(R128) have a synchronous input?
(Yes)
The imege is output 23 pin of UT5
(RT158) is input to ?
(RT158) is input to ?
(Yes)
The signal is output to Pins 32,
33, and 34 of UT5?
33, and 34 of UT5?
(Yes)
That signal is input to Pins 13, 14
and15 of UT12?
and15 of UT12?
Check UT8 and areas around it.
Go to "No sound".
(Yes)
(Yes)
(Yes)
(No)
There are output (20, 21 of
UT10) of MSP3415?
UT10) of MSP3415?
MSP3415 (UT10) is defective.
In the state of reception, it
may not be normal.
may not be normal.
Check YT3, and areas
around it.
around it.
Check UT8 and areas
around it.
around it.
Check UT8, QT8 and
areas around it.
areas around it.
Check UT5 and areas
around it.
around it.
Check UT12 and areas
around it.
around it.
(No)
11.5-V voltage is input to
amplifier (Pin 1 of U27)?
amplifier (Pin 1 of U27)?
Signal is input to input terminal
(Pin 50 of UT10) of MSP3415?
(Pin 50 of UT10) of MSP3415?
(Yes)
Check MSP3415 (UT10) and
circuits around it.
circuits around it.
(Yes)
Speaker and speaker connections
defective. Headphone, headphone
jack connections defective.
defective. Headphone, headphone
jack connections defective.
Signal is input to input terminal
(Pin 47 of UT10) of MSP3415
when monaural signal is input?
(Pin 47 of UT10) of MSP3415
when monaural signal is input?
Check F4 and Q5 and
circuits around them.
circuits around them.
(No)
Amplifier output (W6)?
Check amplifier (U27) and
circuits around it.
circuits around it.
(No)
Check speaker cable and
connector.
connector.
(No)
(No)
(No)
(No)
(No)
(No)
Check signal between TV
tuner SIF output (Pin 15 of
UT1) and UT10.
tuner SIF output (Pin 15 of
UT1) and UT10.
Check signal between TV
tuner AOUDIO output (Pin
16 of UT1) and UT10.
tuner AOUDIO output (Pin
16 of UT1) and UT10.
(No)
No sound
No TV sound
Not operate TELETEXT
Bit missing
Check display data along the flow of each source signal.
TV display
Video display
(composite scart, S, D terminals)
(composite scart, S, D terminals)
PC display
YT3 (generater) 12Mhz is output?
LL-171ME
BLOCK DIAGRAM
5 – 1
CHAPTER 5. BLOCK DIAGRAM
17' WXGA Panel
FLC43XWC8V
CN 3
Inverter
CN2
CN1
J4
W5
J1
Main Board
Keypad Board
Speaker
Power
Adapter
AC INPUT
IR/Headphone
Board
Board
W1
DC/12V
J3
J5 W6
D-Sub W2
ADC
R
G
B
H Sync IN
V Sync IN
G
B
H Sync IN
V Sync IN
Scalar
&
CPU
24
RGB Data bus
Data CLK
H sync
V sync
Data CLK
H sync
V sync
LVDS
transmitter
24
U21
PW166
THC63LVDM83A U24
TO Panel
16
Video
Decoder
VPC 3230
De-interlace
16
PW1231 U29
Flash 8M
memory
memory
U23
29LV800TTC
Frame
memory
memory
U32
EM638165TS
Audio Amp
AN7522 U27
4
VOL-CNTL
DAC
2
U5
M62334
To speaker
Audio
Decoder
PC-Audio Jack
W7
2
W1
DC-Jack
2576 U3
3.3V
2576 U7
5V
12V
TV-tuner
FQ1216ME
UT1
SIF
CVBS
Audio
switch
switch
HC4052 UT4
R/Chroma
3
MSP3415 UT10
R
L
Audio 2
S-video
R
L
AV1 SCART Connecter
Composite 1/
Luma
Luma
BA7645N
Video
switch
switch
T.T.
Decoder
SAA5264 UT5
Y-out
UT8
mixer
3
T.T.
3
3
TA1287 UT2
RGB+T.T..
G
B
U19
MST9883
MST9883
Audio1
Chroma
Luma
CVBS
RGB.
UT7
Composite 2
LL-171ME
BLOCK DIAGRAM
5 – 2
■
CONNECTOR SIGNAL TABLE
[MAIN PWB]
CONNECTOR J3
CONNECTOR J5
CONNECTOR W6
CONNECTOR UT1
CONNECTOR WT2
CONNECTOR WT5
CONNECTOR WT4
CONNECTOR WT3
CONNECTOR WT1
CONNECTOR W5
CONNECTOR J4
CONNECTOR J1
CONNECTOR W7
CONNECTOR W2
CONNECTOR W1
1
HW-PW
2
LED2
3
LED1
4
IRRCVR0
5
GND
6
V50
1
L+
2
OUT+2
3
GND
4
R+
5
OUT+1
1
L+
2
L-
3
R-
4
R+
1
Aerial connector
2
GND
1
BAV99
2
BAV99
3
S-VIDEO_Y
4
S-VIDEO_C
5
GND
6
NC
1
AUDIO-R
2
GND
1
AUDIO-L
2
GND
1
RCA_Yellow_V1
2
BAV99
1
AO_R
2
AI_R
3
AO_L
4
GND_A
5
GND_B
6
AI_L
7
B
8
FS
9
GND_G
10
D2
11
G
12
D1
13
GND_R
14
GND
15
R
16
CTL
17
GND_V
18
GND
19
VO
20
VI
21
F.G
1
NC
2
GND
3
TXO3+
4
TXO3-
5
TXOCK+
6
TXOCK-
7
GND
8
TXO2+
9
TXO2-
10
TXO1+
11
TXO1-
12
GND
13
TXO0+
14
TXO0-
15
TXE3+
16
TXE3-
17
GND
18
TXECK+
19
TXECK-
20
TXE2+
21
TXE2-
22
NC
23
TXE1+
24
TXE1-
25
TXE0+
26
TXE0-
27
GND
28
GND
29
LVCD
30
LVCD
1
KPAD0
2
KPAD1
3
KPAD2
4
KPAD3
5
KPAD4
6
KPAD5
7
KPAD6
8
GND
1
VDD
2
VDD
3
VDD
4
GND
5
GND
6
GND
7
VCON
8
VEE
1
GND
2
PC-L
3
GND
4
PC-R
5
GND
1
GRAI
2
GGAI
3
GBAI
4
GND
5
GND
6
GND
7
GND
8
GND
9
VCCX
10
GND
11
NC
12
RGSA
13
GHSI
14
RVSI
15
RGSL
1
+12V
2
GND
3
GND
4
+12V
LL-171ME
HARDWARE DESCRIPTION
6 – 1
CHAPTER 6. HARDWARE DESCRIPTION
1. OUTLINE OF CIRCUITS
1-1. TV TUNER UT1 (FQ1216M)
The FQ1216M is a TV tuner conforming to the PAL system (Europe) and
the SECAM-L (L') (France). (PIF 38.9MHz)
It operates on the power voltage of 5V (3, 13 pin).
The tuner is controlled by communication between I2C bus (4, 5 pin) and
U21, performing channel selection, broadcasting system selection, and
auto tuning.
A video signal (2Vp-p/100%) is outputted at 12pin and supplied to the video
decoder UT8.
For audio, an FM signal (about 50mVp-p) of SIF is outputted at 11pin and
supplied to the audio processor UT10, where it is decoded.
the SECAM-L (L') (France). (PIF 38.9MHz)
It operates on the power voltage of 5V (3, 13 pin).
The tuner is controlled by communication between I2C bus (4, 5 pin) and
U21, performing channel selection, broadcasting system selection, and
auto tuning.
A video signal (2Vp-p/100%) is outputted at 12pin and supplied to the video
decoder UT8.
For audio, an FM signal (about 50mVp-p) of SIF is outputted at 11pin and
supplied to the audio processor UT10, where it is decoded.
1-2. VIDEO SIGNAL PROCESS (OR)
1-2-1. Composite video signal input selection UT7 (BA7645N)
A video signal is inputted to the composite video signal input pin and
passed to UT7 (4 input 1 output video signal selection IC).
UT7 is switched by the control pins (2, 3, 5 pin) and an output is sent to 10
pin then to the video decoder UT8.
passed to UT7 (4 input 1 output video signal selection IC).
UT7 is switched by the control pins (2, 3, 5 pin) and an output is sent to 10
pin then to the video decoder UT8.
1-2-2. Video decoder UT8 (VPC3230D)
This video decoder selects a composite video signal inputted and the tuner
and an external input pin, Y/C input from S pin, Y, Pb, and Pr signal from D
pin to convert it to Digital Y Pb or Pr signal, outputting to the IP conversion
U29.
The composite video signal is Y/C separated (separation into brightness
signal and color signal).
and an external input pin, Y/C input from S pin, Y, Pb, and Pr signal from D
pin to convert it to Digital Y Pb or Pr signal, outputting to the IP conversion
U29.
The composite video signal is Y/C separated (separation into brightness
signal and color signal).
1-2-3. IP conversion U29 (PW1231)
The PW1231 converts interlace digital Y, Pb, and Pr signals from the video
decoder (UT8) into the progressive digital RGB signal.
decoder (UT8) into the progressive digital RGB signal.
1-2-4. Scaler and CPU U21 (PW166B)
The PW166B converts picture data into a desired picture size and output to
LVDS, and performs as a microprocessor and controls many IC's accord-
ing to the FLASH memory (U23) information.
It also performs PC input and tuner, the external video input PinP (Picture
in Picture), changing the frame rate, and OSD function as additional func-
tions.
LVDS, and performs as a microprocessor and controls many IC's accord-
ing to the FLASH memory (U23) information.
It also performs PC input and tuner, the external video input PinP (Picture
in Picture), changing the frame rate, and OSD function as additional func-
tions.
1-2-5. Video A/D converter U19 (MST9883)
The converter converts analog RGB signals of D-Sub input (W2) into digital
RGB signals and outputs to the scaler.
RGB signals and outputs to the scaler.
1-2-6. LVDS Transmitter U24 (THC63LVDM83A)
This provides an interface between the scaler and the LCD panel.
CMOS/TTL data of 28 bit are converted into LVDS data stream and sent to
the LCD panel.
CMOS/TTL data of 28 bit are converted into LVDS data stream and sent to
the LCD panel.
1-2-7. TeletextUT5 (SAA5264)
The SAA5264 decodes Teletext signals included in the television signals of
PAL and SECAM system.
The composite signal inputted from the tuner (UT1) or the external input pin
through the video decoder (UT8) to 24pin.
The SAA5264 extracts Teletext signals from composite video signals and
converts them into RGB signals and outputs to the video decoder (UT8)
and the mixer (CIRCUIT DIAGRAM UT2, PWB UT12).
Control of Teletext It is carried out by VSDA and VSCL (49, 50 pin).
The output timing of Teletext signals is determined by VSYNC and HSYNC
(36, 37 pin).
PAL and SECAM system.
The composite signal inputted from the tuner (UT1) or the external input pin
through the video decoder (UT8) to 24pin.
The SAA5264 extracts Teletext signals from composite video signals and
converts them into RGB signals and outputs to the video decoder (UT8)
and the mixer (CIRCUIT DIAGRAM UT2, PWB UT12).
Control of Teletext It is carried out by VSDA and VSCL (49, 50 pin).
The output timing of Teletext signals is determined by VSYNC and HSYNC
(36, 37 pin).
1-2-8. Teletext mixer and switching TA1287
( CIRCUIT DIAGRAM UT2, PWB UT12)
( CIRCUIT DIAGRAM UT2, PWB UT12)
The TA1287 is a high-speed switch IC of 2 inputs and 1 output provided
with the matrix circuit of RGB
with the matrix circuit of RGB
3
YUV/IQ.
RGB signals from the external input pin are mixed with RGB signals con-
verted from Y, Pb, and Pr signals of the Teletext decoder IC (UT5) at a
proper ratio, and switching is performed, and the mixed signals are output-
ted to the video decoder (UT8).
verted from Y, Pb, and Pr signals of the Teletext decoder IC (UT5) at a
proper ratio, and switching is performed, and the mixed signals are output-
ted to the video decoder (UT8).
1-2-9. Scart pin (RGB21 pin) WT1
The skirt pin is the AV interface which supports COMPOSITE input, S-
VIDEO input, RGB input, audio input, and TV signal output (video, audio).
VIDEO input, RGB input, audio input, and TV signal output (video, audio).
The mode is controlled as follows ac cording to the control signal from the
connected unit.
connected unit.
1-3. AUDIO SIGNAL PROCESS (OR)
1-3-1. External audio input selection UT4 (74HC4052)
The 74HC4052 is a CMOS switch of 2-circuit and 4-contact.
It switches analog audio input signals from the RCA input pin and the
COMPONENT input pin and outputs audio signal of R_CH and L_CH from
3 and 13 pins. Switch control is performed at 10 pin.
COMPONENT input pin and outputs audio signal of R_CH and L_CH from
3 and 13 pins. Switch control is performed at 10 pin.
1-3-2. Audio processor UT10 (MSP3415G)
The MSP3455G decodes the SIF signal input (50 pin) of the tuner output
into stereo or monaural format and performs audio signal processes such
as sound quality setting (fixing) by Bass and Treble and sound volume set-
ting (fixing) depending on various input sources.
External input signals (41, 42 pin) and PC AUDIO input (44, 45) are
switched and outputted from 20 and 21 pins to the speaker driver.
into stereo or monaural format and performs audio signal processes such
as sound quality setting (fixing) by Bass and Treble and sound volume set-
ting (fixing) depending on various input sources.
External input signals (41, 42 pin) and PC AUDIO input (44, 45) are
switched and outputted from 20 and 21 pins to the speaker driver.
The supported TV broadcast systems are B/G, I, D/K, L (L'), and M (PAL).
This model does not support the NTSC-M system.
This model does not support the NTSC-M system.
1-3-3. Speaker driver U27 (AN7522)
The U27 is a BTL type (push/pull) 3W operational amplifier. It drives 8-ohm
L- and R-channel speakers. The sound signal input through Pins 6, 8 is
output to Pins 2, 4 (Lch) and 10, 12 (Rch) of the speaker, respectively, in
opposite polarity. Pin 9 is a volume control pin and varies with the range of
DC 0 V (mute) to 0.8 V (Max.).
L- and R-channel speakers. The sound signal input through Pins 6, 8 is
output to Pins 2, 4 (Lch) and 10, 12 (Rch) of the speaker, respectively, in
opposite polarity. Pin 9 is a volume control pin and varies with the range of
DC 0 V (mute) to 0.8 V (Max.).
The volume control voltage is output through DAC of the U5 by I2C control.
A voltage of 11 volts is supplied through the ripple filter (regulator) to Pin 1
as the power supply. The output is connected also to the headphone termi-
nal. When the headphone plug is inserted, the speaker is shut off and the
sound is output through the headphone.
as the power supply. The output is connected also to the headphone termi-
nal. When the headphone plug is inserted, the speaker is shut off and the
sound is output through the headphone.
1-3-4. Regulator (LM2576)
The LM2576 is a step-down voltage regulator (3W). The voltage is input
through Pin 1 (7-40 V) and output through Pin 2. The output is then
feedback into Pin 4 to ensure stable voltage output.
The feedback voltage into Pin 4 is compared with the reference voltage
1.23 V of the internal operational amplifier to determine the output voltage.
through Pin 1 (7-40 V) and output through Pin 2. The output is then
feedback into Pin 4 to ensure stable voltage output.
The feedback voltage into Pin 4 is compared with the reference voltage
1.23 V of the internal operational amplifier to determine the output voltage.
1-3-5. Power supply switch U2, U10, U12 (IRF73XX)
The IRF7316 and 7304 are MOSFET 2-channel power supply switch
ICs (ON resistance: 0.06ohm)
When G1 and G2 are put in low level, the input voltage from S1 and S2
When G1 and G2 are put in low level, the input voltage from S1 and S2
are output to D1 and D2.
1-3-6. Protective Zener diode ZD1, ZD2, ZD3 (1N4735)
If the power supply line suffers overvoltage for any reason, a large cur-
rent is passed through the zener diodes to cause shorting to blow out
the fuse in a safe manner. The zener diode may short.
rent is passed through the zener diodes to cause shorting to blow out
the fuse in a safe manner. The zener diode may short.
• 8 pin AV control
Input voltage
LOW (0~2V)
TV Mode
Mid (5~8V)
AV Mode (Wide-screen)
High (9.5~12V)
AV Mode
• 16 pins RGB/COMPOSITE mode switch
Input voltage
LOW (0~0.4V)
COMPOSITE,
S-VIDEO Input MODE
S-VIDEO Input MODE
HIGH (1~3V)
RGB Input MODE
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