PDI-P23 TFT 23 inch LCD - How to enter the service mode, white balance checking, schematic diagram, troubleshooting and more

 

LCD Type :Color Active Matrix TFT
Pixel Pitch :0.372 mm(H) x 0.372 mm(V)
Pixel Format :1366x768 Pixels, RGB Stripe
Active Video Area :508.125mm(H) x 285.696mm(V)
Surface treatment :Haze 44% , Hard coating(3H)
Response Time(Typ) :25mS(Typ)
Viewing Angle<CR≥10> : Hor [Left/Right]  89Deg (Typ) / 89Deg (Typ),
Ver [High(Top)/Low(Bottom)] 89Deg (Type / 89Deg (Typ)
Luminance(Typ) : 450 cd/㎡ (Type)
Contrast Ratio(Typ) : 1200(Type)
Display Color : 16,777,216 Color - True
Back Light : 6 CCFL – U Type

How to enter the service mode

When the EEPROM has been replaced, the SVC data should be restored as the function of individual system and specification.
When the EEPROM has been replaced White Blance Checking.
[ Enter and exit SVC mode ]  Note: into the SVC mode, Initialize with default data.
1) Press 5 Seconds MENU buttons on both TV set and Remote Controller at the same time to get into SVC mode.
2) Press the PR ▲▼ button several times to find SVC Data.
3) Input the corresponding SVC data referring to Table below with the VOL ◀▶ , key.
4) Press TV/AV button to exit SVC mode.

Factory outgoing setting & Initialize with default data (into the SVC mode)

White balance checking WITH DEFAULT FACTORY DATA

Schematic diagram

PCB layout 

Troubleshooting - No Raster

No sound and picture OK

No operation

CIRCUIT DESCRIPTIONS

General Description for 23.01” color TFT LCD TV.
The TFT LCD TV described in the followings is based on a Multi TV system, digital Control display, 23.01" diagonal. The TFT LCD TV is intended to be a finished product, Basically a display device mounted inside an enclosure which will provide the safety Requirements. With the exception of LCD Panel, the display device shall be composed entirely of solid state components.
These components shall have a history of reliable service in identity applications and shall be applied in the circuits.
1. SCALER SECTION.
2. VCT 49xxi SECTION.
3. Video A/D Converter

SCALER SECTION

Device : MST6151
Features: Input supports up to UXGA & 1080P
Panel supports up to SXGA/WXGA
Integrated two-port triple-ADC/PLL
Integrated DVI/HDCP compliant receiver
YUV422 digital video input ports
Dual high-quality scaling engines
Built-in 3-D video de-interlacer
Video-over-graphic PIP
Video-by-graphic split screen
MStarACE advanced picture/color processing engine
Embedded On-screen Display Controller (OSD) engine
Built-in dual-link LVDS transmitter
5-Volt tolerant inputs
Low EMI and power saving features
Supports PWM & GPO controls
208-pin PQFP package
Analog RGB/YPbPr Input Ports
DVI/HDCP Compliant Input Port
Video Input Port
Auto-Configuration/Auto-Detection
Dual High-Performance Scaling Engines
Video Processing & Conversion
On-Screen OSD Controller
 Description
The MST6151 is a high performance and fully integrated graphics processing IC solution for multi-function LCD monitor/TV with resolutions up to SXGA/WXGA. It is configured with an integrated triple-ADC/PLL, an ntegrated DVI/HDCP receiver, a video de-interlacer, two high quality scaling engines, an on-screen display controller, and a built-in output clock generator. By use of external frame buffer, PIP is provided for multimedia applications. It supports de-interlaced full-screen video, video-on-graphic overlay, video-by-graphic split screen, frame rate conversion, and aspect ratio conversion for various video sources. To further reduce system costs, the MST6151 also integrates intelligent power management control capability for green-mode requirements and spread-spectrum support for EMI management.

VCT 49xxi SECTION.

Device : VCT 49xxi
Features : PSSDIP88-1/-2 package
PMQFP144-2 package
Submicron CMOS technology
Low-power standby mode
Single 20.25-MHz reference crystal
8-bit 8051 instruction set compatible CPU
Up to 256 kB on-chip program ROM
WST, PDC, VPS, and WSS acquisition
Closed Caption and V-chip acquisition
Up to 10 pages on-chip teletext memory
Multi-standard QSS IF processing with single SAW
FM Radio and RDS with standard TV tuner
TV-sound demodulation:
Baseband sound processing for loudspeaker channel:
CVBS, S-VHS, YCrCb and RGB inputs
4H adaptive comb filter (PAL/NTSC)
multi-standard color decoder (PAL/NTSC/SECAM)
Nonlinear horizontal scaling “panorama vision”
Luma and chroma transient improvement (LTI, CTI)
Non-linear color space enhancement (NCE)
Dynamic black level expander (BLE)
Scan velocity modulation output
Soft start/stop of H-drive
Vertical angle and bow correction
Average and peak beam current limiter
Nonlinear and dynamic EHT compensation
Black switch off procedure (BSO)
 Description
The VCT 49xxI is an IC family of high-quality singlechip TV processors. Modular design and deep-submicron technology allow the economic integration of features in all classes of singlescan TV sets. The VCT 49xxI family is based on functional blocks contained and approved in existing products like DRX 396xA, MSP 34x5G, VSP 94x7B, DDP 3315C and SDA 55xx.
Each member of the family contains the entire IF, audio, video, display, and deflection processing for 4:3 and 16:9 50/60-Hz mono and stereo TV sets. The integrated microcontroller is supported by a powerful OSD generator with integrated Teletext & CC acquisition including on-chip page memory.

Video A/D Converter

Device: Features:

MST9883CR. *Triple ADC with 12 - 140 MHz Sampling Rate *Integrated line locked PLL generates pixel clock from HSYNC *Integrated 5-bit pixel clock phase adjustment for precise sample timing  control.

*Integrated clamp with timing generator.
*Integrated Brightness & Contrast controls.
*Integrated precision voltage reference.
*Compatible with VGA through SXGA RGB graphics signals, and component TV, DTV and HDTV.

*Pin Compatible with AD9883A.
*Serial port programming interface.

*Mid-Scale Clamping.
*Fully Sync Processing.
*4:2:2 and 4:4:4 Output Format Mode.
*Color space conversion (RGB to YCbCr).
*Internal pattern generator*
*Sawtooth vertical deflection signals for VSYNC input*
*BT656 output format mode*
*Black and mid-level precision clamp and calibration*
*Please see MST9883C Application Note for details.RGB Graphics Processing.
(A/D Converter). 

Description
Most flat-panel monitors and projectors require a digital graphics input in order to accurately scale and display graphics. The huge installed base of computers with analog video graphics interfaces necessitates the use of a graphics digitizer to re-digitize the analog RGB signal before further processing.
* The MST9883CR is a fully integrated analog interface for digitizing high-resolution RGB graphics signals from PC’s and workstations. With a sampling rate capability of up to 140 MHz, it can accurately support display resolutions up to 1280x1024 (SXGA) at 75 Hz. The clamped input circuits provide sufficient band width to accurately digitize each pixel.
* The MST9883CR provides a high performance highly integrated solution to support the digitization process, including the ADC’s, a voltage reference, a PLL to generate the pixel sampling clock from HSYNC, clamping circuits, and programmable offset and gain circuits to provide brightness and contrast controls.
* When the COAST signal is asserted, the PLL will maintain its output frequency when HSYNC pulses are absent, such as during the VSYNC period in some systems.
* A 32-step programmable phase adjustment control (0-360 deg) is provided for the pixel sampling clock to adjust for the difference between the HSYNC edge and RGB pixel edge timing.
* The MST9883CR can send output data through one 24-bit port at the pixel clock rate.
* The MST9883CR can also support RGB to YCbCr conversion.
* The MST9883CR has internal programmable pattern generator for testing.
* The MST9883CR can accept either standard TTL, CMOS levels or sawtooth vertical deflection signals for VSYNC input.