LG CM9760 Schematic

SERVICE MANUAL

CAUTION

BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL.

Internal Use Only

MODEL: CM9760 (CM9650, CMS9760F)

MODEL: CM9760

(CM9760, CMS9760F)

MINI HI-FI SYSTEM

P/NO : AFN77552431

JULY, 2016

CONTENTS

SECTION 1 ........GENERAL

SECTION 2 ........CABINET & MAIN CHASSIS

SECTION 3 ........ELECTRICAL

SECTION 4 ........MECHANISM (DM14AA)

SECTION 5 ........REPLACEMENT PARTS LIST

1-1

SECTION 1

SUMMARY

CONTENTS

SERVICING PRECAUTIONS ............................................................................................................................ 1-3

ESD PRECAUTIONS .........................................................................................................................................1-5

HIDDEN KEY MODE .........................................................................................................................................1-6

SERVICE INFORMATION FOR EEPROM ........................................................................................................ 1-7

PROGRAM DOWNLOAD GUIDE ...................................................................................................................... 1-8

FOTA UPDATE ................................................................................................................................................1-11

SPECIFICATIONS ...........................................................................................................................................1-13

1-2

SERVICING PRECAUTIONS

NOTES REGARDING HANDLING OF THE PICK-UP

1. Notes for transport and storage

1) The pick-up should always be left in its conductive bag until immediately prior to use.

2) The pick-up should never be subjected to external pressure or impact.

Storage in conductive bag

Drop impact

2. Repair notes

1) The pick-up incorporates a strong magnet, and so should never be brought close to magnetic materials.

2) The pick-up should always be handled correctly and carefully, taking care to avoid external pressure and impact. If it is subjected to strong pressure or impact, the result may be an operational malfunction and/or damage to the printed-circuit board.

3) Each and every pick-up is already individually adjusted to a high degree of precision, and for that reason the adjustment point and installation screws should absolutely never be touched.

4) Laser beams may damage the eyes! Absolutely never permit laser beams to enter the eyes! Also NEVER switch ON the power to the laser output part (lens, etc.) of the pick-up if it is damaged.

NEVER look directly at the laser beam, and don’t allow contact with fingers or other exposed skin.

5) Cleaning the lens surface If there is dust on the lens surface, the dust should be cleaned away by using an air bush (such as used for camera lens). The lens is held by a delicate spring. When cleaning the lens surface, therefore, a cotton swab should be used, taking care not to distort lens.

Pressure

Magnet

How to hold the pick-up

Cotton swab

Conductive Sheet

6) Never attempt to disassemble the pick-up. Spring has excess pressure. If the lens is extremely dirty, apply isopropyl alcohol to the cotton swab. (Do not use any other liquid cleaners, because they will damage the lens.) Take care not to use too much of this alcohol on the swab, and do not allow the alcohol to get inside the pick-up.

1-3

Pressure

NOTES REGARDING COMPACT DISC PLAYER REPAIRS

1. Preparations

1) Compact disc players incorporate a great many ICs as well as the pick-up (laser diode). These components are sensitive to, and easily affected by, static electricity. If such static electricity is high voltage, components can be damaged, and for that reason components should be handled with care.

2) The pick-up is composed of many optical components and other high-precision components. Care must be taken, therefore, to avoid repair or storage where the temperature or humidity is high, where strong magnetism is present, or where there is excessive dust.

2. Notes for repair

1) Before replacing a component part, first disconnect the power supply lead wire from the unit

2) All equipment, measuring instruments and tools must be grounded.

3) The workbench should be covered with a conductive sheet and grounded. When removing the laser pick-up from its conductive bag, do not place the pick-up on the bag. (This is because there is the possibility of damage by static electricity.)

4) To prevent AC leakage, the metal part of the soldering iron should be grounded.

5) Workers should be grounded by an armband (1 M)

6) Care should be taken not to permit the laser pick-up to come in contact with clothing, in order to prevent static electricity changes in the clothing to escape from the armband.

7) The laser beam from the pick-up should NEVER be directly facing the eyes or bare skin.

Armband

Resistor (1 M)

Conductive Sheet

1-4

ESD PRECAUTIONS

Electrostatically Sensitive Devices (ESD)

Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field-effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity.

1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test.

2. After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.

3. Use only a grounded-tip soldering iron to solder or unsolder ESD devices.

4. Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can

generate electrical charges sufficient to damage ESD devices.

5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD devices.

6. Do not remove a replacement ESD device from its protective package until immediately before you are ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive materials).

7. Immediately before removing the protective material from the leads of a replacement ESD device, touch the protective material to the chassis or circuit assembly into which the device will by installed.

CAUTION : BE SURE NO POWER IS APPLIED TO THE CHASSIS OR CIRCUIT, AND OBSERVE ALL OTHER

SAFETY PRECAUTIONS.

8. Minimize bodily motions when handing unpackaged replacement ESD devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ESD device).

CAUTION. GRAPHIC SYMBOLS

THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.

THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

1-5

HIDDEN KEY MODE

HIDDEN MODE ENTRANCE KEY EXIT KEY

Version Check EEPROM Initial Option EDIT APD Test Display Front ‘Stop’ + Remote Control Key ‘3’ for 5 s Auto Exit Clip Front ‘Stop’ + Remote Control Key ‘Mute’ for 5 s Auto Exit Disc Lock

On/ Off Power Disc Lock

On/ Off Demo All Key Lock Front ‘Stop’ + Remote Control Key ‘9’ for 5 s Front ‘Stop’ + Remote Control Key ‘9’ for 5 s

Bluetooth Auto Power On/ Off

Child Safe On/ Off

Front ‘Stop’ + Remote Control Key ‘ Front ‘Stop’ + Remote Control Key ‘ Front ‘Stop’ + Remote Control Key ‘

Front ‘Stop’ + Remote Control Key ‘Stop’ for 5 s Front ‘Stop’ + Remote Control Key ‘Stop’ for 5 s Front ‘Stop’ + Remote Control Key ‘Region EQ’ for 5 s

Front ‘Stop’ + Front ‘Open’ for 5 s

Front/ Remote Control Key ‘Power’ for 5 s

Volume 0 (Min) + Front ‘Enter’ for 3 s Volume 0 (Min) + Front ‘Enter’ for 3 s

/ /

for 5 s Remote Control Key ‘ ’ for 1.5 s ’ for 5 s

Auto Exit

’ for 5 s Front ‘Stop’ + Remote Control Key ‘ ’

Front ‘Stop’ + Remote Control Key ‘Region EQ’ for 5 s

Front ‘Stop’ + Front ‘Open’ for 5 s

Front/ Remote Control Key ‘Power’ to SET ‘Power Off’

1-6

SERVICE INFORMATION FOR EEPROM

POWER ON

VFD “NO DISC” status

It is possible at any function. (ex. It is possible at VFD “NO USB” status, too.) This is an example.

Front ‘Stop’ + Remote control ‘ ’

push same timing during 5 s

FLD “OP00-…..”

Move to appropriate position

And make changes with remote control

“ , , , REPEAT” key.

Press ‘Stop’ Key

VFD “WRITE OK”

DETECT NEW EEPROM (OPTION EDIT SCREEN)

NAME

OPT0 OPT1 OPT2 OPT3 OPT4 OPT5 OPT6 OPT7 OPT8 OPT9 OPT10 OPT11 OPT12 OPT13 OPT14

HEX

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Front ‘Stop’ + Remote control ‘ ’

push same timing during 5 s

VFD “E2P CLR”

Completed

1-7

PROGRAM DOWNLOAD GUIDE

1. AUDIO PROGRAM

Download program file name must be MICOM_CM9760_YYMMDDX.HEX

If security program(Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set. Downloading file proceeds in the same way at USB1 function and USB2 function.

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



MICOM UP



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-8

2. CD PROGRAM

Download program file name must be HG690_CM9760_YYMMDDX.bin

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



FIRMWARE



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-9

3. EQ PROGRAM

Download program file name must be EQ_PRG.BIN

Caution:

When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

ON VFD DISPLAY SCREEN

NO USB

Insert USB device at USB function.



EQ UP



FINISH



AUTO POWER OFF

1) (Fast) Format USB device.

2) Copy Firmware file to USB device.

1-10

FOTA UPDATE

Step1. App Connecting

After connecting the bluetooth APP with SET, the user could ﬁ nd the “Device Version info” on Setting tab.

Step2. Device version info

When touch the “Device Version info” button, user could ﬁ nd the current and latest SET version on pop-up menu.

Step3. Select update button

When touch the UPDATE button, user could update the SET ﬁ rmware using FOTA.

Step4. Download from CDN server

Step1 is download from CDN server to smart phone. The progress bar is displayed on bluetooth APP.

1-11

Step5. Transfer FW

Step6. FW ﬂ ash writing

After completed the download from server, smart phone start to transfer the ﬁ rmware to the SET. The progress bar is displayed on bluetooth APP.

Step7. FOTA complete

After completed the download from the smart phone, the SET overwrite the ﬁ rmware to ﬂ ash memory.

When ﬁ nishing the ﬂ ash memory writing, pop-up message about ﬁ nish is displayed and the SET auto power off.

1-12

SPECIFICATIONS

• GENERAL Power requirements Refer to the main label on the unit. Power consumption Refer to the main label on the unit. Networked standby : 0.5 W (If all network ports are activated.) Dimensions (W x H x D) Approx. 450 mm x 160 mm x 355 mm Net Weight Approx. 6,2 kg Operating temperature 5 °C to 35 °C (41 °F to 95 °F) Operating humidity 60 %

• INPUTS Analog audio in (AUX IN) 2.0 Vrms (1 kHz, 0 dB), 600 Ω, RCA jack (L, R) Portable in (PORT. IN) 1.2 Vrms (3.5 mm stereo jack) x 1 Microphone (MIC 1/2) Sensitivity 20 mV (1 kHz), 6.3 mm jack x 2

• TUNER FM Tuning Range 87.5 to 108.0 MHz or 87.50 to 108.00 MHz

• SYSTEM Frequency Response 40 to 20,000 Hz Signal-to-noise ratio More than 75 dB Dynamic range More than 80 dB Bus Power Supply (USB) 5 V 500 mA

• AMPLIFIER (RMS OUTPUT POWER) Total output 3,300 W HIGH 560 W X 2 (6 Ω at 5 kHz, 25 % THD) MID 560 W X 2 (6 Ω at 1 kHz, 25 % THD) LOW 530 W X 2 (6 Ω at 70 Hz, 25 % THD)

• FRONT SPEAKER Type HIGH : 2 Way 2 Speaker MID : 1 Way 1 Speaker LOW : 1 Way 1 Speaker Impedance HIGH : 6 Ω MID : 6 Ω LOW : 6 Ω Rated Input Power HIGH : 560 W MID : 560 W LOW : 530 W Max. Input power HIGH : 1,120 W MID : 1,120 W LOW : 1,060 W Net Dimensions (W x H x D) Approx. 454 mm x 652 mm x 400 mm Net Weight Approx. 22 kg

• Design and specifications are subject to change without notice.

1-13

1-14

SECTION 2

CABINET & MAIN CHASSIS

CONTENTS

EXPLODED VIEWS .........................................................................................................................................2-3

1. CABINET AND MAIN FRAME SECTION ................................................................................................. 2-3

2. MECHANISM DECK SECTION ................................................................................................................ 2-5

3. PACKING ACCESSORY SECTION .........................................................................................................2-7

4. SPEAKER SECTION ................................................................................................................................2-8

2-1

2-2

MAIN

A46

443

274

266

443

468

262

FRONT

FRONT_CTRL

498

271

498

443

271

CABLE1

A52

443

A45

443

467

263

265

443

CABLE2

272

252

A42

250

251

270

254

263

467

264

443

273

275

468

SMPS

A47

498

300

A43

EXPLODED VIEWS

1. CABINET AND MAIN FRAME SECTION

NOTES) THE EXCLAMATION POINT WITHIN AN

EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

1439

A001

1002

1005

1001

1049

1437

1024

1003

1011

1437

1004

1026

1030

1043

1045

A005

A006

1016

1013

1015

1020

1439

1018

1019

1012

2. MECHANISM DECK SECTION

3. PACKING ACCESSORY SECTION

801 Owner’s manual

825 FM Antenna

900 Remote Control

Filter, Ferrite Core

826A

808 Batteries

803 Packing

804 Bag

Packing803

802 Box

4. SPEAKER SECTION

A60L

A60R

SECTION 3

ELECTRICAL

CONTENTS

ONE POINT REPAIR GUIDE ............................................................................................................................3-2

1. NO POWER ............................................................................................................................................3-2

2. NO AMP POWER ...................................................................................................................................3-3

3. NO BOOTING WHEN POWER ON THE SET........................................................................................3-4

4. VFD IS NOT DISPLAYED WHEN POWER ON THE SET ..................................................................... 3-5

5. AUDIO OUTPUT IS SMALL OR NO AUDIO OUTPUT ..........................................................................3-6

6. NO POWER ON (STANDBY LED IS BLINKING) ................................................................................... 3-7

7. SPEAKER NO AUDIO ............................................................................................................................3-8

8. NO BOOTING IN CD/USB FUNCTION .................................................................................................. 3-9

9. NO OPERATION OF MD ...................................................................................................................... 3-14

10. NO SOUND ........................................................................................................................................... 3-19

ELECTRICAL TROUBLESHOOTING GUIDE .................................................................................................3-25

1. POWER SUPPLY ON SMPS BOARD ..................................................................................................3-25

2. SYSTEM PART ..................................................................................................................................... 3-28

3. NO AUDIO CHECK ...............................................................................................................................3-29

WAVEFORMS OF MAJOR CHECK POINT ....................................................................................................3-34

1. DSP (IC501) .......................................................................................................................................... 3-34

2. PWM (IC202) ........................................................................................................................................ 3-35

3. SERVO (IC401) .....................................................................................................................................3-36

4. MOTOR DRIVER (IC400) ..................................................................................................................... 3-37

5. ADC (IC201) ..........................................................................................................................................3-38

6. USB (CN502) ........................................................................................................................................3-38

7. BLUETOOTH (CN504) ..........................................................................................................................3-39

WIRING DIAGRAM ..........................................................................................................................................3-41

BLOCK DIAGRAMS ........................................................................................................................................3-43

1. SYSTEM BLOCK DIAGRAM ................................................................................................................3-43

2. SMPS BLOCK DIAGRAM .....................................................................................................................3-45

CIRCUIT DIAGRAMS ......................................................................................................................................3-47

1. SMPS - POWER #1 CIRCUIT DIAGRAM ............................................................................................3-47

2. SMPS - POWER #2 CIRCUIT DIAGRAM ............................................................................................3-49

3. MAIN - CD DSP CIRCUIT DIAGRAM ...................................................................................................3-51

4. MAIN - ADC/ TUNER/ AUX/ MICOM CIRCUIT DIAGRAM ..................................................................3-53

5. MAIN - RF SERVO CIRCUIT DIAGRAM .............................................................................................. 3-55

6. MAIN - PWM/ AMP LPF CIRCUIT DIAGRAM ...................................................................................... 3-57

7. MAIN - AMP #1 CIRCUIT DIAGRAM ................................................................................................... 3-59

8. MAIN - AMP #2 CIRCUIT DIAGRAM ................................................................................................... 3-61

9. MAIN - SPEAKER LED/ FAN CONTROL CIRCUIT DIAGRAM ...........................................................3-63

10. MAIN - DC_DC/ LDO CIRCUIT DIAGRAM .......................................................................................... 3-65

11. FRONT CIRCUIT DIAGRAM ................................................................................................................3-67

12. FRONT CONTROL CIRCUIT DIAGRAM ..............................................................................................3-69

CIRCUIT VOLTAGE CHART ...........................................................................................................................3-71

1. CAPACITOR VOLTAGE .......................................................................................................................3-71

PRINTED CIRCUIT BOARD DIAGRAMS .......................................................................................................3-73

1. SMPS P.C.BOARD ...............................................................................................................................3-73

2. MAIN P.C.BOARD ................................................................................................................................ 3-77

3. FRONT P.C.BOARD ............................................................................................................................. 3-81

4. FRONT CONTROL P.C.BOARD ..........................................................................................................3-85

3-1

ONE POINT REPAIR GUIDE

1. NO POWER

If the unit doesn’t work by no power problem, repair the set according to the following guide.

1-1. FUSE/ THERMISTOR/ BRIDGE DIODE

1-1-1. Solution

Please check and replace TH900 ~ TH903, BD901 on SMPS board.

1-1-2. How to troubleshoot (Countermeasure)

1) Check if the fuse F901 is open or short-circuit.

2) Check if the NTC thermistor TH900 ~ TH903 is normal or open.

3) Check if the bridge diode BD901 is short-circuit by over current with a digital multimeter.

1-1-3. Service hint (Any picture/ Remark)

< F901 >

If F901 is not short-circuit,

replace it with a same

speciﬁ cations one.

If TH900 ~ TH903 is open,

replace it with a new one.

3-2

< BD901 >

If BD901 is short-circuit,

replace it with a new one.

ONE POINT REPAIR GUIDE

2. NO AMP POWER

If the unit doesn’t work by no ±PVDD problem, repair the set according to the following guide.

2-1. FUSE/ FET

2-1-1. Solution

Please check and replace F911, Q905, Q906 on SMPS board.

2-1-2. How to troubleshoot (Countermeasure)

1) Check if the fuse F911 is open or short-circuit.

2) Check the Drain-Source or Drain-Gate, Gate-Source Resistance of Q905, Q906 with a digital multimeter.  If it is short condition, it’s destroyed. Replace it with a new one.

(Please replace 2 FET at the same time although several FET is OK).

2-1-3. Service hint (Any picture/ Remark)

< F911 >

If F911 is not short-circuit,

replace it with a same speciﬁ cations one.

< Q905, Q906 >

If Q905, Q906 is short-circuit,

replace it with a new one.

3-3

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