Dell E2009W, Руководство по обслуживанию

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Service Manual
11
- Button “Menu” on front bezel connects to U105 (TSUM58EHJ-LF-2) #50 through CN104 #1, U105
#50 Voltage is defined as “Menu”.
- Button “SELECT” on front bezel connects to U105 (TSUM58EHJ-LF-2) #122 through CN104 #4,
U105 #122 Voltage is defined as “SELECT”.
- LED Indicator on Front Bezel
a. When press button “power”, U105 (TSUM58EHJ-LF-2) #123 be send in low Voltage, make
Q107#3 sends out high Voltage , and then to CN01#5 on keypad, LED green on.
b. When in “Suspend” mode, U105 (TSUM58EHJ-LF-2) #124 sends out a low Voltage, make
Q108#3 sends out high Voltage and then to CN01 #7 on keypad, LED Amber ON.
2.3.4 MATAR CHIP U105 (TSUM58EHJ-LF-2)
- U105 (TSUM58EHJ-LF-2) #91~#100 output 8 bit even and #77~#86 output 8 bit odd LVDS digital
data to panel control circuit through CN103.
- U105 (TSUM58EHJ-LF-2) #73 output PPWR ”H” potential to make Q104 conducted, and then
make Q101 conducted, +5V flow to CN103#1~#3 as Panel Vdd .
- U105 (TSUM58EHJ-LF-2) #109 output CCFL_ON/OFF ”L” potential to control Inverter on/off.
- U105 (TSUM58EHJ-LF-2) #125 outputs Brightness “PWM” signals to control CCFL brightness.
- TCLK by Crystal 14.318MHz input to U105 (TSUM58EHJ-LF-2) #128/#127.
- U105 (TSUM58EHJ-LF-2)#108 is RESET signals input pin
Please refer to U105 (TSUM58EHJ-LF-2) Pin Assignments table in page
2.3.5 Regulator Circuit
- +3.3V is generated from Regulator U101 which is supplied by+5V via R101 and through C104
filtering,
-+1.8V is generated from Regulator U102 which is supplied by+3.3V through C106 filtering,
3. FACTORY PRESET TIMING TABLE
Standard Resolution Horizontal Frequency
(KHz)
Vertical Frequency
(Hz)
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
VESA
1680x1050 55.935 59.887
IBM DOS 720 x 400 31.469 70.087
4. Power On/Off Sequency
Hardware power On/Off
When power cord plug into AC socket, Power provides 26V and DC_5V.
DC_5V is main voltage for panel and Regulator U101.
DC_3.3V is coming from Regulator U101, DC_3.3v is main voltage for U105. When DC_3.3V input to
U105 and U105 reset circuit active, U105 all registers will be set to default, that means finish hardware
power on.
When pull out power cord from AC socket,the system shut down instantly for no supply
Software power On/Off
- When press power key, U105 #4 receives low pulse, then U105 (TSUM58EHJ-LF-2) will be wake up