Audio Power Output; I/F Board Circuit - Dell 2209WA Service Manual

Service Manual
D960 & D961, The components including C961,C962,C963,L953 and C964
are used to smooth the current waves, then DC+5V voltage is supplied.
DC 5V supply voltage feed back to PWM controller U950 via,
R964,R968,R963,C969,R965,C968 I951,R962 Used to control the voltage
feedback loop.
R970,R971,R972,R973,C891and ZD971,ZD972,ZD973, Q971 form a
combined OVP circuit.
2.2.5) Audio Power output:(fig.8)
12V audio power is come from linear voltage drop circuit , with output
on/off control circuit.
L930 use for reduce EMI conduct noise. F853 is used for OCP for the LPS test.
2.3 I/F Board Circuit (see the Attachment 2- Schematic)
2.3.1 RGB CAPTURE
- Signal RED,GREEN,BLUE input through CN102 #1,#2,#3, Stop DC via C113,
C114 and C115, and then enter into U105 (TSUMU58EHJ-LF) analog input
PIN #28,#25,#23, and then TSUMU58EHJ-LF deals with signal internally.
D103, D104, D105 are ESD protector to prevent U105 from ESD.
- Signal DDC_SCL (series clock) inputs via CN102#15, and then passes through
ZD106 for ESD protection, goes into EDID EEPROM IC U103 #6.
- Signal DDC_SDA (series data) inputs via CN102#12, and then passes through
ZD103 for ESD protection, goes into EDID EEPROM IC U103 #5.
- Signal TTL vertical sync. (Vsync) inputs via CN102 #14, and then clamped by
ZD105 Zener, passes through R116, and then goes into IC U105
+24V
R931
1K
1/4W
R932
20K 1%
0402
HIGH ON
R935
7 Audio_on_of f
Audio_on_off 10K 0402
R934
C936
1000p/50V
0402
Fig.8
18
+12V
Q930
AP9972
4 3
R936
Q931
10K + C932
PMBT2907A ZD930 470u/25V
2 3 GDZ20B 20V
D932
1N4148
R933
10K
R937 C935
10K 1nF/50V X7R
I930
1 Q932 TL431
MMBT4401
1M
0402
CN853
F853
BNC-2
1
2
5A/125V
R938 L930
39.2K + C933
0402 470u/25V Audio_DET
CHK-091
R939
10K
0402