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9. DVD Part: Introduction of MTK1389D maintenance   

NOTE: MTK1389D is a type of LSIC for DVD decode .MTK1389D IC consists of 
RF,SERVO,DSP,DECODE,VIDEO DAC and AUDIO DAC.

 

1. 

Under normal power supply conditions, the maintenance plan for MT1389D mono-chip is: first the reset 

circuit resets the MT1389D, after the crystal oscillator circuit gave the clock signal to MT1389D, MT1389D will 
start the initialization check for Flash

E

2

PROM

SDRAM, after everything is checked to be normal, it will start 

initialization check for built-in Audio DAC, servo and motor Driver IC . 

2. 

If the all the a.m. parts are good, then MT1389D will send signal to motor Driver to drive the servo 

system

pick up then to generate DVD light for collection, tracing the main shaft to check if there is any disc, and 

confirm if it is CD format or DVD format disc. If the disc is in DVD format, the system will read the data from the 
disc directly; if it is in CD format built-in servo will drive the CD laser to send out CD light and read the data, the 
data then will be amplified through built-in RF amplifier and sent to MT1389D decode part for data processing, 
released by MPEG and resolved into video data and audio data, then they will be returned to analog signals 
through    built-in VIDEO DAC

AUDIO DAC. 

 

Decoder section 

3. 

There is power supply, clock and reset, but the system does not work. 

1

 

Check if all the address wires required for FLASH are exist, and if they are in normal status, 

especially check if the A0~A15 of FLASH have normal signals, if there aren’

t, then inspect MT1389D to see if 

there is faulty soldering. If there are normal signals at A0~A15, check if the address data signal of MT1389D 
and SDRAM is normal. If it is normal, then check the signal at A16~A19 of MT1389D; if there are also signals, 
then check the video output  wires and AV filter circuit; if there is no signal, then check the corresponding pins 
of MT1389D to see if there is any short circuit, break or faulty soldering. 

4. 

System in normal operation, but the audio has no sound. 

1

 

Because the AUDIO DAC is built in MTK1389D IC.you need to check the lower passing amplifying 

circuit and the MUTE circuit at the back of the LPF circuit. Also check if there is any power supply to the LPF 
circuit. 

2

 

Check if the power supply voltage required for playing is at normal level. 

 

Servo Section 

5. 

After the LOGO of the machine shows normally, there is no OSD display. This problem mainly is caused 

by the abnormality built-in RF and servo, possible problems may be: 

1

 

Built in RF and its surrounding circuits have problems. 

2) 

Servo part of MT1389D has problems. 

6.   OSD display is normal

while there is no action of servo part

feeding motor does not work, main shaft does 

no turn, possible fault status are: 

1) 

The corresponding signals giving by MT1389D to DMSO

FMSO are missing, the reason may be the 

problem of MT1389D or the communication between MT1389D and motor Driver IC SA5668. 

2)   

Not output from Motor Driver, the reason may be the problem on motor Driver or its corresponding 
circuit. 

 

7. 

Servo part in good status, while there is no pick up action

no light, no focus

 

1

  No light, check the power supply

power supply for pick up

, or the light producing driving circuit to see 

if they are in normal status. 

 

  

      2

  No focus, check MT1389D to see if there is signal output from FOSO

TRSO. 

Secondly, check motor driver to see if there is F+

F-

T+

T-signal output. 

Thirdly, check the external corresponding circuit of the motor driver to see if there is any problem. 

 

8. 

All the servo part has action, while it cannot read out the disc 

1

   Check MT1389D if there is RF net picture output, if there isn’

t, then it must be the problem of 

MT1389D and external surrounding circuits, it there is output, then it might the problem of MT1389D 
and its surrounding circuits. 

2

  There is RF signal

but not in normal status

then check MT1389D and surrounding circuits. 

3

  Everything is normal, but the disc cannot be read out, check MT1389D and its surrounding circuit 

 
 
 
 
 
 
 

 
 

Summary of Contents for 21T07

Page 1: ...EATURES l DVD TV 20 COMBO l AUTO TUNE 181 CHANNES l DVD VCD SVCD CD CD R CD RW JPEG MP3 COMPATIBLE l FORMATO DE VIDEO 4 3PS 4 3LB l DOLBY AC 3 DECODE l PANATAL LOCK l ATSC TUNER CAUTION READ THIS MANUAL CAREFULLY TO DIAGNOSE TROUBLE CORRECTLY BEFORE OFFERING SERVICE TV 8888 88 ...

Page 2: ... precautions 3 2 TV block diagram 4 3 Replacement of memory IC 5 4 Service adjustment 5 5 ICs functional description 8 6 Test point waveform 10 7 All ICs voltages 11 8 Purity convergence adjustment 12 9 DVD maintenance 14 ...

Page 3: ...not check high voltage by drawing an arc Use a high voltage meter or a high voltage probe with a VTVM Discharge the picture tube before attempting meter connection by connecting a clip lead to the ground frame and connecting the other end of the lead through a 10kO 2W resistor to the anode button 8 When service is required observe the original lead dress Extra precaution should be given to assure ...

Page 4: ... 4 2 Block diagram R2J10165GC series with stereo intercarrier sound demodulator ...

Page 5: ...d press VOLUME VOLUME key to make data adjustment of corresponding factory menus Press EXIT key to exit factory mode Focus adjustment 1 Receive a crosshatch signal 2 While watching the screen adjust the FOCUS VR on the FBT to make the vertical and horizontal lines as fine and sharp as possible Geometrical adjustment Receive NTSC standard complete pattern signal Adjustment steps a Adjust V SC S eme...

Page 6: ...0 IN YUV Black level offset R GB YUV 128 128 0 IN YUV Black level offset G BB YUV 128 128 0 IN YUV Black level offset B RD YUV 128 128 0 IN YUV White point R BD YUV 128 128 0 IN YUV White point B CR PEDDOT 0 15 8 CR benchmark voltage adjust CB PEDDOT 0 15 8 CB benchmark voltage adjust CRCB PED ON 0 1 1 YUV benchmark voltage switch CRCB GAIN UP 0 1 0 YUV benchmark voltage plus P4 Items Preset Remar...

Page 7: ...mory 3 else C_10164 5 070119 ATV software edition P8 Items Preset Remark Description AUTO N PM PN 0 1 1 AUTO N PM PN function choice AUTO N N4 P 0 1 0 AUTO N PM PN function choice PAL 0 1 0 PAL 0 N 1 Y NTSC 0 1 1 NTSC ON Y OFF N N443 0 1 1 NTSC4 43 ON Y OFF N P358 0 1 0 3 58PAL 0 N 1 Y PAL M 0 1 0 PAL M ON Y OFF N PAL N 0 1 0 PAL N ON Y OFF N P9 Items Preset Remark Description AV2 0 1 1 AV2 1 Y 0 ...

Page 8: ...3 SP02 PWM SP03 PWM 4 SP03 PWM TEST0 5 TEST0 P04 AD2 6 P04 AD2 P05 AD1 7 P05 AD1 P06 TIM31 8 P06 TIM31 AFT AD0 9 SIF auto phase control DEF VCC 8 0V 10 8V POWER V RAMP 11 V RAMP VRAMP CAP 12 VRAMP CAP AFC 1 FIL 13 SIF auto phase control filter DEF VCC 5 0V 14 5V POWER H OUT 15 Horizontal SIGNAL OUT FBP IN 16 FBP IN DEF GND 17 GND VRAMP AGC 18 VRAMP AGC Cb IN YcbCr 19 Cb IN YcbCr Cr IN YcbCr 20 Cr ...

Page 9: ... 8 7V 54 VREG VCC 8 7V MNITOR OUT 55 MNITOR OUT MCU RESET 56 MCU RESET P20 57 P20 P21 58 P21 P22 59 P22 HLF 60 HLF VHOLD 61 VHOLD CVIN 62 CVIN P26 AD6 63 P26 AD6 AD6 P27 64 AD6 P27 P35 TIM21 65 P35 TIM21 CNVSS 66 CNVSS TEST1 Note1 67 TEST1 Note1 TEST2 Note2 68 TEST2 Note2 VSS 69 VSS FILT 70 FILT VDD 71 VDD P36 72 P36 P17 INT3 AD4 73 P17 INT3 AD4 P16 INT2 AD3 74 P16 INT2 AD3 P15 INT1 75 P15 INT1 P1...

Page 10: ... 1 Inverting input Poutput stage supply 6 Output stage supply SUPPLY VOLTAGE 2 Supply voltage Input 7 Non inverting input Flyback generator 3 Flyback generator GND 4 Ground or negative supply Output 5 Output 5 U101 Tuner PIN Function PIN Function 1 Nc 7 5V 2 Tu 8 IFA1 3 Rf agc 9 IF AGC 4 SCL 10 IFD 1OUT 5 SDA 11 IFD 2 OUT 6 Btl 6 Test point Waveforms 5Vpp 0 9Vpp 1 3Vpp H H 1Vpp V CRT KB CRT KG CRT...

Page 11: ... 68 2 86 0 2 74 0 17 1 47 1 47 2 53 3 09 5 3 3 3 45 2 4 3 43 3 15 3 43 PIN 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 V 2 47 8 03 2 57 2 49 2 59 8 87 0 42 4 9 4 94 4 95 3 82 1 96 0 33 2 9 4 95 4 94 PIN 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 V 4 95 0 0 16 4 95 0 1 76 4 95 4 95 4 94 4 83 0 03 4 95 3 52 3 7 3 58 3 73 STV9302A PIN 1 2 3 4 5 6 7 V 2 993 26 8 14 57 0 1 96 26 05 2 991 TFA98...

Page 12: ...o the centre of the screen Fig 3 8 Move the deflection yoke forward and fix the position of the deflection yoke so that the whole screen will become green 9 Insert the wedge to the top side of the deflection yoke so that it will not move 10 Input a crosshatch signal 11 Verify that the screen is horizontal 12 Input red and blue raster signals and make sure that purity is properly adjusted CRT WEDGE...

Page 13: ...t convergence DYNAMIC CONVERGENCE ADJUSTMENT 1 Move the deflection yoke up and down and overlap lines in the periphery Fig 2 2 Move the deflection yoke left to right and overlap the lines in the periphery Fig 3 3 Repeat 1 and 2 above and make the best convergence After adjustment fix the wedge at the original position Fasten the retainer screw of the deflection yoke Fix the 6 magnets with glue FRO...

Page 14: ...onding pins of MT1389D to see if there is any short circuit break or faulty soldering 4 System in normal operation but the audio has no sound 1 Because the AUDIO DAC is built in MTK1389D IC you need to check the lower passing amplifying circuit and the MUTE circuit at the back of the LPF circuit Also check if there is any power supply to the LPF circuit 2 Check if the power supply voltage required...

Page 15: ...15 Sincere Forever Haier Group ...

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