Dell 2209WA - UltraSharp - 22" LCD Monitor, Руководство по обслуживанию

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Service Manual
20
- LED Indicator on Front Bezel
a. When press button “power”, U105 (TSUMU58EHJ-LF) #123 be send in low
Voltage, make Q107#3 sends out high Voltage to CN104#5 , and then to
keypad, LED blue on.
b. When in “Suspend” mode, U105 (TSUMU58EHJ-LF) #124 sends out a low
Voltage, make Q108#3 sends out high Voltage to CN104#7 , and then to
keypad, LED Amber on.
2.3.4 MAIN CHIP U105 (TSUMU58EHJ-LF )
- U105 (TSUMU58EHJ-LF ) #86~#77 output 8 bit even and #100~#91 output 8
bit odd LVDS digital data to panel control circuit through CN103.
- U105 (TSUMU58EHJ-LF ) #50 output ”H” potential to make Q104
conducted, and then make Q101 conducted, +5V flow to CN103#1~#3 as
Panel Vdd .
- U105 (TSUMU58EHJ-LF) #109 output CCFL_ON/OFF ”H” potential to
control Inverter on/off.
- U105 (TSUMU58EHJ-LF) #110 output ”H” potential to control Inverter
power on/off.
- U105 (TSUMU58EHJ-LF) #125 outputs Brightness “PWM” signals to control
CCFL brightness.
- TCLK by Crystal 14.318MHz input to U105 (TSUMU58EHJ-LF) #128.
- U105(TSUMU58EHJ-LF) #108 is RESET signals input pin
Please refer to TSUMU58EHJ-LF Pin Assignments table in page
2.3.5 Regulator Circuit
- +5V is from switching power supply .
- +3.3V is generated from Regulator U101 which is supplied by+5V via R101
and through C101 filtering, C102 and C105 is 3.3V which supplies toU102
、
U106
、
U103
、
U201
、
U105
、
U108output filtering.
- +1.8V is generated from Regulator U102 which is supplied byU101-3.3V
through C106 filtering.TheU102 output1.8V via FB105 send to U105.
3. FACTORY PRESET TIMING TABLE
Standard Resolution Horizontal
Frequency (KHz)
Vertical
Frequency (Hz)
VESA
640 x 480 31.469 59.940
640 x 480 37.500 75.000
800 x 600 37.879 60.317
800 x 600 46.875 75.000
1024 x 768 48.363 60.004
1024 x 768 60.023 75.029
1152x864 67.500 75.000
1280x1024 48.483 60.042
1280x1024 60.087 75.034
1680x1050 55.935 59.887