LG CM7420 Service Manual Download Page 68

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3-51

3-52

2. MAIN SYSTEM BLOCK DIAGRAM

IC407

BU9543KV

RF+ SERVO

IC408

S3053

Motor Drive

A,B,C,D,E,F,PD

USB_HUB_DP/DN

IC200

CS5346

IC501

MLC3700

MCS LOGIC

SPDO/SLDO/FOD/TRD

LOAD

,SLED

SPIN

,TR

OP_SW,CL_SW,UP_SW,DN_SW,D_SENSE

MOT_MUTE,CLOSE,OPEN

ADC_DATA

IC502

M12L6464A

SDRAM

IC503

MX25L8006

1MB(S/F)

M00_15/A00_16

DRM_WEN/CAS/RAS/SEL/CLK/CKE

SF_DI/DO

SF_CS/SCK

ADC_PWM_CLK/BCK/LRCK/DAT,

ADC_RST,DAC_MCLK

PT_L/R

AUX_L/R

AUX

USB1

Portable

CD_

/W,

SY,

_16M

BSYQ

CD_

MCK

RCK

/DA

TUNER_L/R

USB_RESET/SCL/SDA

IC504

USB2512

USB HUB

USB2

IC605

S4308

MIC

IC603

AK5358

MIC_SIG0

MIC_I_DATA

TUNER

FRONT

IC101

MICOM

LC87F085

VFD_STB/CLK/DO/RST

STANDBY_LED,VOL_LED1~7
USB_PWR_CTRL

IC100

EEPROM

E2PROM_CLK/DATA

IC602

PS9854

PWM

F/L

F/R

SPEANA

IC701

AMP IC

TAS5631

IC702

AMP IC

TAS5631

325Wx2

SW1

PWM_LRCK/BCK (DAC_DATA)

ADC_PWM_DATA/CLK, EXT_MUTE,DSP_PWM_RST

16.9344MHz

15pF

MIC_SIG

MIC_MCLK/BCK/

LRCK

8(&

&+)

4GEGKXGT

KEY1~3,JOG_A/B

VOL_A/B,REMOCON

8QNWOG

-G[

9.8304MHz

33pF

32.768KHz

22pF/27pF

CD_DVD_DI

CD_DVD_CE/

CLK/DO/RST

MIC_O_DATA

AMP_PDN

AMP_CLIP1/0, AMP_OTW/SD, AMP_READY, AMP_PROTECT

A/+%

8A7%1/

8A%&8%%

8A4(8A%&8

8A%&

8A75$

8A#&%

P/UP

kljrGG

tljohupzt

8%%

19.2MHz

22pF

Summary of Contents for CM7420

Page 1: ... MODEL CM7420 CM7420 CMS7520F CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL MODEL CM7420 CM4520 CMS7520F SERVICE MANUAL 2 1 0 2 JULY 75814469 N F A O N P Website http biz lgservice com Internal Use Only ...

Page 2: ...CONTENTS SECTION 1 GENERAL SECTION 2 CABINET MAIN CHASSIS SECTION 3 ELECTRICAL SECTION 4 REPLACEMENT PARTS LIST 1 1 ...

Page 3: ...Y 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 1 AUDIO PROGRAM 1 8 2 CD PROGRAM 1 9 3 EQ PROGRAM 1 10 SPECIFICATIONS 1 11 1 2 ...

Page 4: ... 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 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...

Page 5: ...eplacing 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...

Page 6: ... 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 materia...

Page 7: ...ROM Option by SKIP 3 Clear EEPROM Front Key STOP RCU Key SKIP 4 Edit EEPROM Front Key STOP RCU Key SKIP You can change the digit of option by SKIP You can edit 0 f by REPEAT or PLAY PAUSE key 5 Bluetooth DUT Front Key STOP RCU Key PROGRAM Bluetooth model only 6 Power Disc Lock On Off CD Function Only Active Front Key STOP RCU Key EQ 7 Amp Clip On Off Front Key STOP RCU Key Mute Amp Clip Mode Chang...

Page 8: ...appropriate position and make changes with remote control REPEAT Press STOP key FLD write ok Remote control Front STOP at a time FLD E2P CLR Completed NAME OP0 OP1 OP2 OP3 OP4 OP5 OP6 OP7 OP8 OP9 DETECT NEW EEPROM OPTION EDIT SCREEN HEX 09 00 00 00 00 69 80 05 10 00 1 7 SERVICE INFORMATION FOR EEPROM ...

Page 9: ...n download the file to your set 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 READ FIRMWARE WRITE 00 100 UPDATED POWER OFF AUTOMATICALLY When completed remove usb device 1 8 PROGRAM D...

Page 10: ... security software then download the file to your set 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 READ FIRMWARE FINISH When completed remove usb device POWER OFF ON 1 9 ...

Page 11: ...ftware then download the file to your set 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 READ EQ DOWNLOAD UPDATED POWER OFF AUTOMATICALLY When completed remove usb device 1 10 ...

Page 12: ... stereo jack TUNER FM Tuning Range 87 5 to 108 0 MHz or 87 50 to 108 00 MHz AM Tuning Range 522 to 1 620 kHz 520 to 1 710 kHz or 522 to 1 710 kHz AMPLIFIER Stereo mode 325 W 325 W 4 Ω at 1 kHz THD 10 Surround mode Front 325 W 325 W 4 Ω at 1 kHz THD 10 CD Frequency Response 40 to 20 000 Hz Signal to noise ratio 75 dB Dynamic range 80 dB FRONT SPEAKER Type 2 Way 2 speaker Impedance 4 Ω Rated Input P...

Page 13: ...1 12 MEMO ...

Page 14: ...SECTION 2 CABINET MAIN CHASSIS CONTENTS EXPLODED VIEWS 2 3 1 CABINET AND MAIN FRAME SECTION CM7420 2 3 2 MECHANISM DECK SECTION DP 12A 2 5 3 PACKING ACCESSORY SECTION 2 7 4 SPEAKER SECTION 2 8 2 1 ...

Page 15: ...2 2 MEMO ...

Page 16: ...CABLE7 CABLE5 MIC 464 464 464 464 464 A B E A B F H D G K I J K C A46 265 462 464 462 462 A47 266 MAIN SMPS 274 271 F E H G VOLUME VFD CABLE6 267 251 254 252 CABLE4 276 275 464 272 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 ...

Page 17: ...2 MECHANISM DECK SECTION DP 12A MEMO A02 439 018 013 017 014 020 016 440 015 015B 015A 435 A01 026 001 002 012 012 037 012A 019 442 442 A03 003 010 ...

Page 18: ...801 Owner s Manual 804 Bag 802 Box 808 Battery AAA 900 Remote Control 824 AM Loop Antenna 825 FM Wire Antenna 803 Packing 803 Packing AA A 3 PACKING ACCESSORY SECTION ...

Page 19: ...A60 4 SPEAKER SECTION FRONT SPEAKER CMS7520F ...

Page 20: ...T 3 37 4 DIGITAL AUDIO AMP CHECK 3 41 WAVEFORMS 3 42 WIRING DIAGRAM 3 47 BLOCK DIAGRAMS 3 49 1 SMPS BLOCK DIAGRAM 3 49 2 MAIN SYSTEM BLOCK DIAGRAM 3 51 CIRCUIT DIAGRAMS 3 53 1 SMPS CIRCUIT DIAGRAM 3 53 2 MAIN MICOM CIRCUIT DIAGRAM 3 55 3 MAIN PWM FILTER CIRCUIT DIAGRAM 3 57 4 MAIN IR AMP CIRCUIT DIAGRAM 3 59 5 MAIN DSP USB IPOD CIRCUIT DIAGRAM 3 61 6 MAIN RF SERVO CIRCUIT DIAGRAM 3 63 7 MAIN ADC C...

Page 21: ... clockwise for the volume up The volume level LEDs around the master volume will be turned on more and more while turning it clockwise for the volume up YES NO Is there any sound from the selected input source AUX IN USB TUNER or CD Disc Refer to a device s instruction manual and then check if there is sound output from it connecting another audio system YES NO Are the sound spectrum level LEDs on...

Page 22: ... s instruction manual and then check if there is sound output from it connecting another audio system YES NO Are the sound spectrum level LED s on the left and right side of the front panel being changed up and down according to the sound input gain The sound spectrum level LED s will be turned on off repeatedly at regular intervals A speaker cable might be short circuited with the chassis ground ...

Page 23: ...nstruction manual and then check if there is sound output from it connecting another audio system YES NO Are the sound spectrum level LED s on the left and right side of the front panel being changed up and down according to the sound input gain The sound spectrum level LED s will be turned on off repeatedly at regular intervals A speaker cable might be short circuited with the chassis ground Be c...

Page 24: ...ength of the radio station too week Make sure to tune the station manually YES NO Are the sound spectrum level LED s on the left and right side of the front panel being changed up and down according to the sound input gain The sound spectrum level LED s will be turned on off repeatedly at regular intervals A speaker cable might be short circuited with the chassis ground Be careful not to be shorte...

Page 25: ...he owner s manual YES NO After selecting a track number using the SCAN or DISC button press PLAY button and turn the master volume clockwise for the volume up The volume level LEDs around the master volume will be turned on more and more while turning it clockwise for the volume up YES NO Is the sound quality good to listen to the music Make sure to clean CD discs with a commercially available cle...

Page 26: ...the speaker terminals on the unit and the speakers Maker sure to connect the cables to each specified connector tightly on the unit Connect the woofer cables to the WOOF SYSTEM connectors on the rear panel YES NO The sound is output from the speakers Sound OK NO YES TRAINING MASTER ...

Page 27: ...supported MP3 WMA music file requirement Refer to the owner s manual YES NO After selecting a track number using the SCAN button press PLAY button and turn the master volume clockwise for the volume up The volume level LEDs around the master volume will be turned on more and more while turning it clockwise for the volume up YES NO Are the sound spectrum level on the left and right side of the fron...

Page 28: ...oblem referring to the service manual YES NO Is the Standby LED turned off after pressing the Power button on the remote control Replace the batteries with new ones if the remote control doesn t work YES NO Are the messages displayed in the following order on VFD HELLO VOLUME 15 FUNCTION The SMPS might be not able to supply the power to drive the VFD Refer to the service manual to fix it YES NO Is...

Page 29: ...Countermeasure 1 Check if the fuse F901 is open or short circuit 2 Check if the bridge diode BD901 is short circuit by over current with a digital multi meter 3 Check if the NTC thermistor TH901 and TH902 is normal or open 1 1 3 Service hint Any picture Remark F901 If F901 is not short circuit replace it with a same specifications one TH901 TH902 If TH901 or TH902 is open replace it with a new one...

Page 30: ...951 D952 ZD951 on SMPS board 1 2 2 How to troubleshoot Countermeasure 1 Check the Anode Cathod Voltage of D951 D952 with a digital multi meter it is normally 0 2 0 3 V If it doesn t have any voltage it s destroyed Replace it with a new one 2 Check if ZD951 is short circuit If it is short circuit and then replace it with a new one 1 2 3 Service hint Any picture Remark SMPS schematic diagram ...

Page 31: ...eck the 3 7 VA to CN102 CN103 and CN104 in standby mode If there is no 3 7 VA check the SMPS 2 Check 5 6 VA 12 VA FL FL and 32 V when power on the set If the set doesn t work regardless of what the KEY1 changes high to low while pressing the power button X100 and X101 work normally but if you can not power on the set replace the IC101 with a new one on the main board 2 1 3 Service hint Any picture...

Page 32: ...d 3 1 2 How to troubleshoot Countermeasure 1 Check if VKK 32 V FL and FL are output from SMPS to VFD via the main board 2 Check if 3 3 VA enters IC301 3 Check if the IC101 outputs VFD_RST VFD_CLK VFD_STB and VFD_STB to the front board 4 Check if pin P1 15G of DIG301 If there is no signal replace IC301 with a new one If there is no problem replace VFD with a new one 3 1 3 Service hint Any picture R...

Page 33: ...f IC505 pin2 on MAIN board If IC505 pin2 about 4 9 V D501 Input 5 6 VA doesn t come out check 5 6 VA from SMPS board 2 If IC505 pin2 about 4 9 V is normal check the PWR_CTRL IC505 pin1 is high about 3 3 V If PWR_CTRL isn t high check pin63 of IC101 R149 R503 3 If PWR_CTRL is high check R592 R593 and if there s no defective component then replace IC505 4 If 3 3 V VCC33 is normal check output pin2 4...

Page 34: ...ace X501 on MAIN board 4 2 2 How to troubleshoot Countermeasure 1 If 3 3 V 1 2V is normal check Reset High of IC501 pin153 on MAIN board If MAIN_RESET isn t high check MICOM IC101 pin59 2 If MAIN_RESET is high check the soldering status of 12 MHz crystal X501 3 If the crystal X501 doesn t oscillate check R541 R542 C517 C518 around crystal X501 If there s no defective component then replace X501 4 ...

Page 35: ...ard 4 3 2 How to troubleshoot Countermeasure 1 If the crystal X501 does oscillate check serial flash IC503 on MAIN board Check pin8 VCC pin6 CLK pin1 CS pin2 DO pin5 DI of below waveform 2 If pin1 2 5 6 8 doesn t come out check damping resistor R511 R513 R514 R515 of IC503 If damping resistor of IC503 is OK then replace IC503 it need to download program 3 After change IC503 if It is still not belo...

Page 36: ... and replace IC502 on MAIN board 4 4 2 How to troubleshoot Countermeasure 1 Check below waveform soldering status of SDRAM IC502 on MAIN board If pin17 CAS pin18 RAS pin19 CS pin38 CLK pin29 address pin2 DQ doesn t come out check damping resistor R508 R506 R504 R507 2 If resistor is OK then replace IC502 SDRAM 3 After change IC502 if It is still not below waveform check IC501 DSP IC 4 4 3 Service ...

Page 37: ...n Please check and replace IC501 on MAIN board 4 5 2 How to troubleshoot Countermeasure 1 After check them by previous pages about NO Booting if the set is still no booting Check soldering status of IC501 Check boot strap option R598 R594 R597 of IC501 DSP IC 2 If below bootstrap waveform doesn t come out then replace IC501 DSP IC 4 5 3 Service hint Any picture Remark IC501 R594 PGPB12 Yellow R598...

Page 38: ...e SPDO signal from Pin16 of IC407 If no signal check 3 3V RF and X402 2 Check the SP SP from IC408 to CN405 for driving SPinDLE motor It is about 3 6 Vp p If no signal check 1 8 V and 5 V for IC408 3 Check if the FFC cable is solidly connected between CN405 and MD 4 Check the MD If the spindle motor is sort circuit or has any trouble it can not rotate CD discs Please check the function after chang...

Page 39: ...n15 of IC407 If no signal check 3 3 V RF and X402 2 Check the SLED SLED from IC408 to CN405 for driving SPINDLE motor It is about 2 9 Vp p If no signal check 1 8 V and 5 V for IC408 3 Check if the FFC cable is solidly connected between CN405 and MD 4 Check the MD If the sled motor is sort circuit or has any trouble it can not move the pick up module Please check the function after changing another...

Page 40: ...8 If no signal check 1 8 V 5 V to IC408 2 Check LOAD from IC406 to CN405 for driving the tray open close motor It is about 3 85 Vp p If no signal check 5 V to IC406 If it has any trouble replace it with a new one 3 Check if the FFC cable is solidly connected between CN405 and MD 4 Check the MD If the tray motor is sort circuit or has any trouble it can not open or close the tray Please check the f...

Page 41: ...m be positioned in the center of a track on CD disc 1 Check the TRD signal from Pin14 of IC407 If no signal check 3 3 V RF and X402 2 Check T T from IC408 to CN404 for driving the tracking actuator If no signal check 1 8 V and 5 V for IC408 3 Check if the FFC cable is solidly connected between CN404 and MD 4 Check the MD If the pick up module has any trouble it can not move the laser beam on the l...

Page 42: ...ep a regular interval with the surface of a CD disc 1 Check the FOD signal from Pin13 of IC407 If no signal check 3 3 V RF and X402 2 Check F F from IC408 to CN404 for driving the focusing actuator If no signal check 1 8 V and 5 V for IC408 3 Check if the FFC cable is solidly connected between CN404 and MD 4 Check the MD If the pick up module has any trouble it can not move the laser beam on the t...

Page 43: ... flow I2S audio signal Interface DAC_BCK IC501_pin4 IC507_pin14 16 R821 of IC801 Beat option IC602_pin4 DAC_LRCK IC501_pin5 IC507_pin5 7 R820 of IC801 Beat option IC602_pin5 44 1 kHz DAC_DATA IC501_pin6 R817 next to IC801 Beat option IC602_pin6 9 DAC_MCLK IC501_pin3 R818 next to IC801 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is di...

Page 44: ...ormal 5VU of IC3U01 pin3 doesn t come out then replace IC3U01 2 Check USB D from main board to USB board a Check USB_HUB_DN DP signals to IC501 pin16 17 b Check USB1 2_DN DP signals from IC504 to CN502 pin1 2 4 5 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is distorted or no signal replace it with a new one 3 Check if Digital audio A...

Page 45: ...HUB_DN DP signals to IC501 Pin16 18 b Check USB1 2_DN DP signals from IC504 to CN502 Pin1 2 4 5 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is distorted or no signal replace it with a new one 3 Check if Digital audio AMP block Item 6 3 is normal 6 2 2 3 Service hint Any picture Remark kT G G G Gju WY kRG G G G Gju WY USB USB Board T ...

Page 46: ...3 Check 12 for driving the gate of AMP IC a All the powers are normal but if 12 V is low there is possible for AMP IC to be damaged b Remove a ferrite bead among FB703 FB707 and FB713 one by one When removed a ferrite bead if 12 V is recovered the IC connected to it was damaged c Replace the IC with a new one 4 Check the impedance between SPK GND and SPK GND a If the impedance is 0 Ω the IC must b...

Page 47: ...k the following I2S signal flow from IC501 to IC602 Refer to Item 6 1 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is distorted or no signal replace it with a new one 5 Check if the digital audio AMP block is okay Refer to Digital Audio AMP guide on Item 6 3 If AMP is damaged replace it with a new one 6 4 3 Service hint Any picture Re...

Page 48: ... IC202 If is NG replace it a new one 6 Check the following I2S signal flow from IC501 to IC602 Refer to Item 5 1 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is distorted or no signal replace it with a new one 7 Check if the digital audio AMP block is okay Refer to Digital Audio AMP guide on Item 6 3 If AMP is damaged replace it with ...

Page 49: ...om IC202 to IC501 If no signal check 5 V 3 3 V ADC for IC202 If is NG replace it a new one 4 Check the following I2S audio signal flow from IC501 to IC602 Refer to Item 5 1 If there is any trouble check the power for each IC The power is normal but if the signal waveform to the IC is distorted or no signal replace it with a new one 5 Check if the digital audio AMP block is okay Refer to Digital Au...

Page 50: ...MIC_BCK MIC_LRCK is entered from IC507 to IC603 and DAC_MLCK from IC501 to IC603 Check if MIC_DATA is entered from Pin9 of IC603 to pin7 of IC602 If no signal check 5 V 3 3 V for IC603 If it is abnormal change replace it a new one 6 Check the following I2S signal flow from IC603 to IC602 If there is any trouble check the power for each IC If the signals are abnormal replace it a new one 7 Check if...

Page 51: ...GUIDE 1 POWER SUPPLY ON SMPS BOARD YES YES YES YES No output 5 7 VA Power line of MAIN PCB is short Replace F901 same fuse Replace D904 Replace BD901 Replace D933 D937 NO NO NO NO F901 normal D904 normal BD901 normal D933 D937 normal ...

Page 52: ...UIDE YES YES YES YES YES No output 12 V Power Line of Main PCB is short Replace F901 same fuse Replace D904 Replace BD901 Replace D934 D935 Replace IC931 NO NO NO NO NO F901 normal D904 normal BD901 normal D934 D935 normal IC931 normal ...

Page 53: ...RICAL TROUBLESHOOTING GUIDE YES YES YES YES No output FL FL Check soldering of PN901 Check 12 V output P CTRL Replace ZD931 Replace D931 D932 Replace FR931 NO NO NO NO P CTRL OK ZD931 OK D931 D932 OK FR931 short ...

Page 54: ...No AMP Output Check soldering of CN902 Check 3 3 V P CTRL Replace ZD912 ZD913 Replace D951 D952 Replace D904 Q901 PC911 Is the VCC supplied to IC911 Pin7 ZD912 ZD913 OK D951 D952 OK NO NO NO NO NO P CTRL OK Q901 D904 OK YES YES YES YES YES ...

Page 55: ...D LD3V01 LD3V8 Check MAIN board Replace DIG301 HELLO Display on FLD OK Volume LED LD3V01 LD3V8 Turn on When turn the volume count is change NO NO NO NO NO NO NO NO NO CN301 cable connection OK CN3V01 pin22 12 V OK Port P1 G15 of DIG301 is OK CN3V01 pin23 24 signal OK CN301 Pin8 9 10 data signal OK CN301 Pin15 16 17 power OK 2 SYSTEM PART YES YES YES YES YES YES YES YES YES ...

Page 56: ...eck Loading motor Check IC501 OPU driving Focusing Tracking OK Check OPU Pick up module Is motor impedance about 12 Ω IC407 Pin34 35 36 I2S output signal OK Can disc insert IC501 Pin95 96 97 I2S input signal OK Disc reading OK NO NO NO NO NO NO NO NO NO IC407 RF Servo signal OK Focusing Tracking Sled Signal OK LOAD OK YES YES YES YES YES NO YES YES YES A 3 NO AUDIO PART ...

Page 57: ...B_D output signal OK NO NO IC3U01 USB power 5 VU OK YES A A When insert USB IC504 Pin1 2 3 4 USB_D signal OK NO YES YES YES YES YES AUX Check audio cable Replace IC202 Check IC501 NO NO NO IC202 Pin7 8 AUX input signal OK IC202 Pin41 ADC data output signal OK IC202 Pin42 43 44 I2S input signal OK ...

Page 58: ...T IN input signal OK IC202 Pin41 ADC data output signal OK IC202 Pin42 43 44 I2S input signal OK TUNER Check IC501 Replace IC202 Check 3 3 V of TU101 IC202 Pin42 43 44 I2S input signal OK IC202 Pin41 ADC data output signal OK NO NO NO TU101 TUNER_L R output signal OK YES A IC202 Pin23 24 TUNER_L R input signal OK NO YES YES YES ...

Page 59: ...Check IC507 Check IC501 Check IC501 Check IC801 NO NO NO NO NO NO IC501 Pin4 5 6 I2S data output signal OK IC507 Pin7 14 BEAT_LRCK BCK output signal OK IC507 Pin2 17 DAC_BCK LRCK input signal OK IC501 Pin6 BEAT_DAC_DATA output signal OK IC801 I2S input signal OK IC801 BEAT_DATA output signal OK ...

Page 60: ...1 Check L701 L702 L704 L705 Check L708 L709 L710 L711 Check IC602 Replace IC701 Replace IC702 12 VA 50 V Power voltage OK IC602 PWM data output signal OK IC602 I2S input signal OK IC701 FL FR input signal OK IC701 SPK_FL FR output OK IC702 SPK_SW output OK IC702 SW1 input signal OK NO NO NO NO NO NO YES YES YES YES YES YES YES YES YES OK ...

Page 61: ...3 42 1 SERVO WAVEFORM WAVEFORMS Figure 1 1 CD 16M IC407 pin31 Figure 1 2 Servo FE TE FOD RF IC407 pin61 pin62 pin63 IC408 pin1 FE TE FOD RF ...

Page 62: ...VEFORM Figure 2 1 SP SP for driving Spindle motor IC408 pin17 pin18 Figure 2 2 SL SL for driving Spindle motor IC408 pin11 pin12 Figure 2 3 LO LO for driving Tray motor IC408 pin9 pin10 tv jsvzl tv vwlu svR svT SP SL SP SL ...

Page 63: ... PATH WAVEFORM Figure 3 1 CD I2S IC407 pin34 pin35 pin36 Figure 3 2 IC501 pin95 pin96 pin97 Figure 3 3 IC602 PWM IC pin4 pin5 pin6 pin9 BCK BCK BCK LRCK LRCK LRCK DATA DATA DATA Figure 3 4 AUDIO_L R AUDIO_L AUDIO_R ...

Page 64: ...3 45 Figure 4 1 ADC I2C IC202 pin1 pin2 Figure 4 2 ADC I2S IC202 pin41 pin42 pin43 pin44 4 ADC WAVEFORM CLK DATA MCK BCK LRCK DATA ...

Page 65: ...3 46 5 USB WAVEFORM 6 CRYSTAL WAVEFORM Figure 5 USB D D CN502 pin1 pin2 pin4 pin5 Figure 6 12 MHz crystal IC501 pin27 pin28 p v D D ...

Page 66: ...GT 6GTOKPCN CTPGUU 2 0 CTPGUU 2 0 QP 2 0 QP 2 0 4 5 481 QP 2 0 QP 2 0 2 0 9CHGT 2 0 MOT P UP ZPGkljrGG tljohupzt 8 2 OO 2 OO 9CHGT 2 9CHGT 2 6TCPU 8 2 8QNWOG 75 2 QP 2 0 QP 2 0 8 2QTVCDNG LCEM KE LCEM 9CHGT 2 0 2QTV KE 2 9CHGT 2 0 9CHGT 2 0 7 2 OO 2 OO 2 9 2 9 2 9 2 9 WIRING DIAGRAM ...

Page 67: ...P FL FR TRANS MAIN AMP Filter Section Varistor Resistor Line Filter Thermistor Rectifier Circuit Bridge CAPACITOR AMP Power NCP1252 Control IC FET U TZY XY U W AC Snubber msORVTP rr STR A6053 for Main Power MAIN TRANS pwvkGVG ziGVGtwlnVGkjkj vwhtwVmhu mk mk wTj ys ...

Page 68: ... DATA TUNER_L R USB_RESET SCL SDA IC504 USB2512 USB HUB USB2 IC605 S4308 MIC IC603 AK5358 MIC_SIG0 MIC_I_DATA TUNER FRONT IC101 MICOM LC87F085 VFD_STB CLK DO RST STANDBY_LED VOL_LED1 7 USB_PWR_CTRL IC100 EEPROM E2PROM_CLK DATA IC602 PS9854 PWM FL FR F L F R SPEANA IC701 AMP IC TAS5631 IC702 AMP IC TAS5631 325Wx2 SW1 PWM_LRCK BCK DAC_DATA ADC_PWM_DATA CLK EXT_MUTE DSP_PWM_RST 16 9344MHz 15pF MIC_SI...

Page 69: ...T USED THIS WAY IMPLEMENTATION OF THE LATEST SAFETY AND PERFORMANCE IMPROVEMENT CHANGES INTO THE SET IS NOT DELAYED UNTIL THE NEW SERVICE LITERATURE IS PRINTED NOTE 1 Shaded parts are critical for safety Replace only with specified part number 2 Voltages are DC measured with a digital voltmeter during Play mode A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T CAUTION Danger if fu...

Page 70: ...3 55 3 56 2 MAIN MICOM CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T MICOM EAX64550401_Rev1 2 SD 1 2012 01 09 ...

Page 71: ...3 57 3 58 3 MAIN PWM FILTER CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T PWM EAX64550401_Rev1 2 SD 2 2012 01 09 ...

Page 72: ...3 59 3 60 4 MAIN IR AMP CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T AMP EAX64550401_Rev1 2 SD 3 2012 01 09 ...

Page 73: ...3 61 3 62 5 MAIN DSP USB IPOD CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T DSP EAX64550401_Rev1 2 SD 4 2012 01 09 ...

Page 74: ...3 63 3 64 6 MAIN RF SERVO CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T RF SERVO EAX64550401_Rev1 2 SD 5 2012 01 09 ...

Page 75: ...3 65 3 66 7 MAIN ADC CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T ADC EAX64550401_Rev1 2 SD 6 2012 01 09 ...

Page 76: ...3 67 3 68 8 MAIN BEAT BOX CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T BEAT BOX EAX64550401_Rev1 2 SD 7 2012 01 09 ...

Page 77: ...3 69 3 70 9 FRONT VFD CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T VFD EAX64632201_Rev1 3 2 SD 2012 02 23 ...

Page 78: ...3 71 3 72 10 FRONT VOLUME CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T VOLUME EAX64632301_Rev1 3 2 SD 2012 02 23 ...

Page 79: ...3 73 3 74 11 FRONT MIC PORTABLE CIRCUIT DIAGRAM A 1 2 3 4 5 6 7 8 9 10 11 12 B C D E F G H I J K L M N O P Q R S T MIC PORTABLE EAX64632401_Rev1 3 2 SD 2012 02 23 ...

Page 80: ...ENDER TAEJIN VIN 2 Vout 4 Spec Vin Max 26V Vout Max 25V Measured volt Vin 5 65V Vout 3 29V 16 IC506 CP CHIP MFI337S3959 TYPE 8P VENDER APPLE VCC 9 Spec VDD 1 62V 5 5V Measured volt VDD 3 29V 17 IC507 BUFFER 74AHC244FT TYPE 20P VENDER Philips VCC 20 Spec Vcc 2 0V 5 5V Measured volt VDD 3 29V 18 IC509 LDO AZ1117BH 1 2TRE1 TYPE 3P VENDER BCD VIN 3 Vout 2 Spec Vin Max 12V Vout 1 176 1 224V Measured vo...

Page 81: ...4 C462 47uF 16V 3 32 35 C431 47uF 16V 1 65 36 C467 3 3uF 50V 1 74 37 C492 47uF 16V 3 32 38 C4H6 100uF 6 3V 1 83 39 C485 220uF 16V 5 08 40 C210 10uF 16V 2 47 41 C211 47uF 16V 4 98 42 C213 47uF 16V 4 97 43 C221 100nF 16V 3 28 No Location Value Capacitor uF Voltage Spec Measured voltage 44 C244 100uF 16V 5 61 45 C231 47uF 16V 5 08 46 C236 10uF 16V 5 19 VFD 01 C243 47uF 16V 12 1 02 C303 47uF 50V 7 2 0...

Page 82: ...3 79 3 80 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...

Page 83: ...3 81 3 82 SMPS P C BOARD BOTTOM VIEW NOTE Warning Parts that are critical with respect to risk of fire or electrical shock ...

Page 84: ...3 83 3 84 2 MAIN P C BOARD TOP VIEW ...

Page 85: ...3 85 3 86 MAIN P C BOARD BOTTOM VIEW ...

Page 86: ...3 87 3 88 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...

Page 87: ...3 89 3 90 4 FRONT_MIC PORTABLE P C BOARD TOP VIEW BOTTOM VIEW ...

Page 88: ...3 91 3 92 5 FRONT_VOLUME P C BOARD TOP VIEW ...

Page 89: ...3 93 3 94 FRONT_VOLUME P C BOARD BOTTOM VIEW ...

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