SANYO - LCD-DP55441 - SERVICE MODE - POWER SUPPLY - CIRCUIT

SANYO - LCD-DP55441 - SERVICE MODE - POWER SUPPLY - CIRCUIT

 

Adjustment instruction
At any input source then press the remote controller buttons “<”, “EXIT” and “>” to enter factory mode. During Factory menu, if “MENU” or “EXIT” key is pushed, system will exit factory mode.
Source Calibration
1.Set the TV input source to YPbPr; ASTRO-859 signal setting to PG2 program number 933(1080i). (PG2 mode Timing 933 and Pattern 924 100% Color Bar.)

2. Entering into factory Mode: Press up or down key of remote control to select “Auto Calibration”, Press OK  key to start.

Source calibration performed automatically when finished that will show OK.

Color Temperature Adjustment & Check
Set input source.
Set the signal generator Astro-859 timing to PG2-924 on Video & YPbPr, PG2-860 on HDMI, and PG2-963 on PC. Pattern sets 956 on all of the source.

Then press Astro-859 “FORMAT” key and DOWN key, then adjust RGB value to R:204, G:204, B:204

In factory mode OSD menu, select “Color Temperature” item, press “OK” key to enter the item. R, G, B drive values are set for Warm, Medium, and Cool independently.

Set Color Temperature for “Warm”, “Medium” and “Cool”

If the x and y value are larger than specification,
Decrease Red drive from default value.
Increase Blue drive from default value.
If the x or y or both x and y value is/are smaller than specification.
Decrease Blue drive from default value
According to a x and y value, please following adjustment of 1 or 2.
1. If x value is higher than spec Decrease Red drive from default value.
2. If y value is higher than spec, Increase Blue drive from default value

Exit Factory Mode:
After finishing adjusting color temperature, press [MENU] or [EXIT] to exit factory mode.

Items of Factory menu
Vendor may customize design and add adjustment items Factory menu as far as all required items are included.

Press up and down key can move high light item from Color Temperature Warn -> Color Temperature Medium -> Color Temperature Cool ->Preset Channel-> Source Calibration -> Reset to Default. The NVRAM Clear and Reset to Default items will have a check dialog “YES” and “NO” to do or not. Push “Enter” key can select high light item function. (Press left and right can adjust value) Display model name, firmware version and released date on top.

1) Color Temperature for Warm
Press up or down key can select high light item function.
Press enter key to enter the item.
Following data for color temp shall be edited manually.
-R, G, B data for each preset.
-Press “Up” or “Down” key to select “R”, “G”, “B” item
-Press “Left” or “Right” key to set the “R”, “G”, “B” value.
-Press “MENU” or “EXIT” item to exit to factory mode
2) Color Temperature for Medium
Press up or down key can select high light item function.
Press enter key to enter the item.
Following data for color temp shall be edited manually.
-R, G, B data for each preset.
-Press “Up” or “Down” key to select “R”, “G”, “B” item
-Press “Left” or “Right” key to set the “R”, “G”, “B” value.
-Press “MENU” or “EXIT” item to exit to factory mode
3) Color Temperature for Cool
Press up or down key can select high light item function.
Press enter key to enter the item.
Following data for color temp shall be edited manually.
-R, G, B data for each preset.
-Press “Up” or “Down” key to select “R”, “G”, “B” item
-Press “Left” or “Right” key to set the “R”, “G”, “B” value.
-Press “MENU” or “EXIT” item to exit to factory mode
4) Time Clear
Press up or down key can select high light item function.
Press “Left” & “Right” key to select the item.
The timer on bottom is to record power on time for panel life.
It was set one time on production only.
5) Preset Channel
This is for factory to do some tests.
6) NVRAM Clear
Initialize program’s default values to NVRAM for following adjustment items accuracy.
In factory mode it is the first and important step to make sure all values are default value and correct.
- Reset settings: Channel table, Mode table (H/V Position, Clock, Phase), Source dependent setting (Contrast, Brightness etc.), Common setting (Volume, Language etc.), Parental Control (Rating, Password etc), Closed Caption. To avoid a mistake initial process after factory setting is done. This item will have a check dialog to do the initial or not.
NOTICE: After this item is processed, the DUT needs to be powered off then AC powered off.
7) Full Power
This is for power consumption testing.
To measure the maximum power consumption of TV set, we adjust the value of following items to maximum.

- Video: Contrast maximum value, Brightness maximum value, Backlight maximum value.
- Audio: Volume maximum value.
Press right key to turn on Full Power and OSD stay display until press enter key to recover from Full Pow
8) Source Calibration
Auto Calibration (gain/offset) must be adjusted color by firmware automatic adjustment in PC, and Video3(Component) input source.
This item will have a result dialog “OK” or “NG”.
9) Reset to Default
This function is same as “NVRAM Clear”, but it will power off automatically after processing this function
10) RF Burn In
Use “snow” pattern for burn in. Selected items are “On” and “Off”. While turn on burn in mode, firmware will automatically turn off “Auto power off” function.
If there is no power supply suddenly, firmware will re-enter burn in mode automatically when power supply is back.
Pressed the “Power” key, firmware will automatically turn off burn in mode.
- Burn in mode: Source is “TV”, Input Configuration is “Antenna” and channel is NTSC channel 2

11) Protocol Switch
This is for debugging only. It is no use for service.

12) EDID Write
This is for writing EDID on the VGA source.

13) MEMC Demo Mode
To separate screen into two parts that left side is 60Hz and right side is 120Hz for display.
14) MEMC Level
Changing MEMC level to Weak, Medium or Strong.

Performance check
1. TV function
Connect RF to the center signal source, enter Channel menu → Channel Scan, check if there are channels be skipped, check if the picture and speaker are normal.
2. AV/S-Video terminals Input AV/S-Video signal, check if the picture and sound are normal.
3. YPbPr/YCbCr terminal
Input YPbPr signal (VG-859 signal generator), separately input the YUV signals listed in table4 and check if the display and sound are normal at any situation (power on, channel switch and format convert, etc.)

4. PC(VGA) terminal
Input PC(VGA) signal (VG-859 signal generator), separately input the signals listed in table5 and check the display and sound. If the image is deflection of the Horizontal and Vertical, select Menu->PC->Auto Adjust to perform auto-correct.

5. HDMI terminal
Input HDMI signal (VG-859 signal generator), separately input the signals listed in table6 and check the display and sound (32KHz, 44.1KHz, 48KHz) at any situation (power on, channel switch and format convert, etc.)

6. other functions check
a) Check the turn on/turn off timer, sleep timer, picture/sound mode, OSD, stereo and analog TV Close Caption, VChip, etc.

Working principle analysis of the unit

1. NTSC/ATSC signal flow:
Antenna reception NTSC/ATSC signal will be send to tuner U32, then Tuner will be demodulating and output differential IF+ IF- signal  These differential IF+ IF- signal will send to the master control IC U1 to video/MPEGII decode, deinterlace and scaler, then output LVDS level drive for panel display. The differential signals will be fed into U1 to demodulate audio signals , after demodulating, preamplifying, bass adjusting and volume control, the sound signal will be transform into digital I2S signal by scaler IC and sent to digital amplifier U5 amplifying, then output to speaker.
2. AV VIDEO signal flow

Video path AV signal switch by menu “Inpput list” via terminal socket, the signal and the Video1 path AV signal will be fed to U1 to perform video decode, de-interlace and scaler, then output LVDS drive level for panel display. Audio signal from AV terminal via matched resistance is fed to U1 to bass adjust and volume control, the sound signal will be transfered into digital I2S signal by scaler IC and sent to digital amplifier U5 amplifying, output to speaker.
3. PC/YPrPb signal flow
PC and the Video2 and Video3 path YPbPr signal are via terminal sent to U1 A/D conversion, output R/G/B of 24 bit to back end module to digital decode, image scale, then send to LVDS level drive for panel display. Sound signal of PC/YPrPb te rmina l via matched resistance a n d sent to U1 to bass adjust and volume control, the sound signal will be transform into digital I2S signal by scaler IC and sent to digital amplifier U5 amplifying, then output to speaker.
4. HDMI signal flow
HDMI video signal via terminal sent to U1 to digital decode, image scale, then output LVDS drive level for panel display. HDMI audio signal via decoder built-in terminal sent to U1 is fed to back end to bass adjust and volume control, the sound signal will be transform into digital I2S signal by scaler IC and sent to digital amplifier U5 amplifying, then output to speaker.
5. MEDIA signal flow
The JPEG file via USB terminal send to U1 to MPEG decode , image scale , then output LVDS drive level for panel display .

POWER SUPPLY CIRCUIT 

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