Saturday, April 09, 2016

Dell1800FP - LD803H LG CL29-Chassis – 18 inch LCD monitor – Schematic Diagram

Dell1800FP -  LD803H LG CL29-Chassis - 18 inch LCD monitor -  Power supply regulator (SMPS) -  Circuit Diagram - Main board - Adjustments
Type: TFT SXGA LCD
Size: 18.1inch
Pixel Pitch: 0.2805(H) x 0.2805(V)
Color Depth : 8-bit, 16,777,216 colors
Backlight Unit: 6-CCFL (Cold Cathode Fluorescent Lamp)
AC Input: AC 100~240V, 50/60Hz, 1.0A (Built-in Power)
Operating Frequency
Horizontal: 30 ~ 80 kHz
Vertical: 56 ~ 85Hz
DELL 1800FP Driver Board LD803H 6870T494A12
Micom and LVDS schematics
Memory and Power (SMPS) circuits
Power Part.
This part consists of the one 5V, two 3.3V and one 2.5 regulators to convert power which is provided 12V, 5V in Power Board.
12V is provided for inverter, 5V is provided for Micom and LCD Panel.  Also, 5V is converted 3.3V and 2.5V by regulator. Converted power is provided for IC in the main board.
Inverter
The inverter converts from DC12V to AC 700V and operate back-light lamp of module.
Adjustment Start
1) Display any pattern at any Mode.
2) Run alignment program for LD803H on the IBM compatible PC.
3) Select EEPROM → ALL INIT command and Enter.
4) This will make all data to default state.
5) Select COMMAND → PRESET START command and Enter.
Adjustment for White Balance
1) Display Black pattern at SXGA/60Hz.
2) Set External Bright to MAX position and Contrast to MAX Position.
3) Select PRESET START → BIAS CAL command and Enter.
4) No attempt to manually adjust, BIAS data is automatically adjusted and saved to the EEPROM.
5) Display Full White pattern at SXGA/60Hz.
6) Select DRIVE CAL command and Enter.
7) 9300K are automatically adjusted and saved to the EEPROM.
8) Select PRESET EXIT command and Enter.
Adjustment for EDID
1) Use this procedure only when there is some probelm on EDID data.
2) Connect the D-sub cable.
3) Select EEPROM → EDID(A) WR command and Enter.
4) DVI to D-sub cable.
5) Select EEPROM → EDID(D) WR command and Enter.
Exploded view