background image

 

 

11 

 

7. IC voltages 

 
TDA8377 

PIN 

10 

11 

12 

13 

14 

15 

16 

  V 

3.8 

3.6 

3.3 

3.5 

4.4 

5.1 

1.8 

0.18  0.17 

2.3 

PIN 

17 

18 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

29 

30 

31 

32 

  V 

0.5 

0.7 

0.8 

1.9 

1.9 

3.9 

3.8 

1.6 

3.2 

2.3 

2.3 

0.2 

PIN 

33 

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46 

47 

48 

  V 

0.5 

0.3 

1.7 

2.4 

3.4 

3.9 

3.3 

3.6 

1.4 

2.5 

2.5 

2.5 

PIN 

49 

50 

51 

52 

53 

54 

55 

56 

57 

58 

59 

60 

61 

62 

63 

64 

  V 

1.9 

5.0 

2.4 

2.4 

2.4 

3.1 

3.2 

1.8 

1.7 

3.2 

5.1 

3.3 

 

TDA8357 

PIN 

  V 

0.8 

0.7 

16 

6.9 

43 

7.2 

0.3 

7.2 

 

AN 7522N 

PIN 

10 

11 

12 

 

  V 

10 

4.4 

4.4 

2.75 

1.4 

1.4 

0.35 

4.4 

4.4 

 

 

24C08/PCF8598

 

PIN 

  V 

5.1 

3.2 

5.1 

 
 
 

 
 
8. PURITY / CONVERGENCE ADJUSTMENT 

                    

                                             

                          

Summary of Contents for IS-TVDVD20A

Page 1: ...r Television SERVICE MANUAL IS TVDVD20A l FEATURES l DVD TV 21 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 ...

Page 2: ... Replacement of memory IC 5 4 Service adjustment 5 5 ICs functional description 8 6 Test point waveform 10 7 All ICs voltages 10 8 Purity convergence adjustment 11 9 DVD maintenance 13 10 List of Parts 14 11 Circuit diagram Attached 12 Exploded view Attached ...

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 10kΩ 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 TDA8377PS N2 series with mono intercarrier sound demodulator ...

Page 5: ...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 PAL standard complete pattern signal Adjustment steps a Adjust VSL to the centre horizontal line just appear...

Page 6: ...t 0 A 0BRI Listen Brightness 0 A 0COL Listen Colour 50 A 0SHP Listen Sharpness 50 A 1CON Soft Contrast 45 A 1BRI Soft Brightness 45 A 1COL Soft Colour 50 A 1SHP Soft Sharpness 50 A 6 Picture preset 2 2CON Standard Contrast 75 A 2BRI Standard Brightness 50 A 2COL Standard Colour 50 A 2SHP Standard Sharpness 60 A 3CON Dynamic Contrast 85 A 3BRI Dynamic Brightness 60 A 3COL Dynamic Colour 60 A 3SHP D...

Page 7: ...on Description Preset Remark Bit 6 HALFTONE 1 Enable 1 EA Bit 5 IDENT_SENSITIVE 1 EA Bit 4 HCO 1 Enable 0 EA Bit 3 LOGO 1 EA Bit 2 TILT 0 EA Bit 1 SPANISH 1 EA Bit 0 ROMANIA 0 EA 5 OP5 Bit Function Description Preset Remark Bit 7 STORE_AV 1 Enable 1 EA Bit 6 OSO 1 Enable 0 EA Bit 5 SOFR_CHANGE 1 Enable 0 EA Bit 4 FADE 1 Enable 0 EA Bit 3 SOUND_M 1 Enable 0 EA Bit 2 SOUND_I 1 Enable 0 EA Bit 1 SOUN...

Page 8: ...N DESCRIPTION STAND BY output 1 In STAND BY mode low level Power OFF For Power ON this pin will be high SCL 2 I2 C bus clock line SDA 3 I2 C bus data line TUNING 4 tuning Voltage Vt PWM output KEY 5 Control keys input SYSTEM 6 TV system control VOL 7 Sound Volume control PWM output MUTE 8 Sound mute output VSSC P 9 Digit ground for μ controller core and periphery CTL 10 DVD power control STANDBY 1...

Page 9: ... B input U B Y input PB input BCLIN 49 Beam current limiter input BLKIN 50 Black current input RO 51 Red output GO 52 Green output BO 53 Blue output VDDA 54 Analog supply of Closed Caption decoder and digital supply of TV processor 3 3 V VPE 55 Ground VDDC 56 Digital supply to core 3 3 V OSCGND 57 Oscillator ground supply XTALIN 58 Crystal oscillator input XTALOUT 59 Crystal oscillator output RESE...

Page 10: ... output V FEEDBACK 9 Vertical feedback GND 5 Ground 5 U101 Tuner PIN Function PIN Function 1 AGC 7 5V 2 vacant 8 vacant 3 Gnd 9 Vt 33V 4 SCL 10 Gnd 5 SDA 11 IF Out 6 5V 6 Test point Waveforms 5Vpp 0 9Vpp 1 3Vpp H H 1Vpp V CRT KB CRT KG CRT KR 95Vpp 95Vpp 95Vpp H H H TDA8377PIN53 2 5Vpp 2 5Vpp 3 8Vpp H H H TDA8377PIN52 TDA8377 PIN51 TDA8377 PIN33 TDA8377 PIN34 0 8Vpp V TDA8377 PIN21 TDA8377 PIN22 T...

Page 11: ...5 36 37 38 39 40 41 42 43 44 45 46 47 48 V 0 5 0 3 0 1 7 2 4 3 4 8 3 9 0 3 3 0 3 6 1 4 2 5 2 5 2 5 PIN 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 V 1 9 5 0 2 4 2 4 2 4 3 1 0 3 2 0 1 8 1 7 0 3 2 5 1 3 3 5 TDA8357 PIN 1 2 3 4 5 6 7 8 9 V 0 8 0 7 16 6 9 0 43 7 2 0 3 7 2 AN 7522N PIN 1 2 3 4 5 6 7 8 9 10 11 12 V 10 4 4 0 4 4 2 75 1 4 0 1 4 0 35 4 4 0 4 4 24C08 PCF8598 PIN 1 2 3 4 5 6 7 8 V 0 0 5 ...

Page 12: ...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 DEFLECTION YOKE...

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: ...udio DAC are exist if there is signal missing then check the signal line between MT1379 and Audio DAC If the line is connected properly but there is no signal then check if there is any welding problem at the corresponding pins of MT1379 If it is still OK it is probably the problem on MT1379 itself 2 All the required signals are exist while there is no audio output Then you need to check the lower...

Page 15: ...15 Sincere Forever ...

Reviews: