Dell S1909WXf Service Manual page 11

D854 is used to rectify the inducted current. R860 and C861 are used to store energy when
current is reversed. The parts including C862, C865, C864 and L853 are used to smooth the
current waves that are from D854, and then 16V voltage is supplied.
D856 is used to rectify the inducted current. R869 and C876 are used to store energy when
current is reversed. The parts including C856, C870, C859, C872 and L855 are used to smooth the
current waves that are from D856, and then 5V voltage is supplied.
16V and 5V supply voltage feed back to PWM controller U830 via R871, R872, R868 and
I850,I851.R865,C866 and C855 used to control respond time.
When 16V output or 5V output come out of SPEC , D857,D858 and Q851 will be operated, via
I850 ,U850 will be in Auto Restart mode until the matter is got rid of .
2.3 I/F Board Circuit (see the Attachment 2- Schematic)
2.3.1 RGB CAPTURE
- Signal RED,GREEN,BLUE input through CN101 #1,#2,#3, Stop DC via C101, C102 and
C103, and then enter into U104 (TSUM56BWHK-LF) analog input PIN #59,#56,#54, and
then TSUM56BWHK-LF deals with signal internally. D101, D102, D103 are ESD protector to
prevent U104 from ESD.
- Signal DDC_SCL (series clock) inputs via CN101#15, and then passes through ZD104 for
ESD protection, goes into EDID EEPROM IC U102 #6.
- Signal DDC_SDA (series data) inputs via CN101#12, and then passes through ZD105 for
ESD protection, goes into EDID EEPROM IC U102 #5.
- Signal TTL vertical sync. (Vsync) inputs via CN101 #14, and then clamped by ZD103 Zener,
passes through R116, and then goes into IC U104 (TSUM56BWHK-LF) #64.
- Signal TTL horizontal sync. (Hsync) inputs via CN101 #13, and then clamped by ZD102
Zener, passes throughFB104 & R115, and then goes into IC U104 (TSUM56BWHK-LF) #63.
- CN101#5 is defined as cable detect pin, this detector realize via R113 and U104#26, and
fig.7
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Service Manual