JVC AV-27F704/BSA Service Manual page 22

2.3 TECHNINAL INFORMATION
2.3.1 SYSTEM BLOCK DIAGRAM
2.3.2 MAIN MI-COM (CPU) PIN FUNCTION
Pin
I/O
Pin name
No.
1 AFT2 I Not used
2 AFT1 I AFT voltage for tuner (Tuning frequency control)
3 KEY I Key scan for front control [No signal : H]
4 uP DVss - GND
I CPU reset
5 Reset
6 Xout O CPU system clock : 8MHz oscillation
7 Xin I CPU system clock : 8MHz oscillation
8 TEST - GND
9 uP_DVDD - 5V
10 AGC_MUTE O AGC muting for tuner (when channel select) [Muting : H]
11 UP_VVss - GND
12 TV_HGND - GND
13 FBP_SCP I Flyback pulse (H. pulse)
14 Hout O H. drive (oscillation)
- 9V (for H. oscillation start)
15 H_Vcc_9V
H. AFC filter
16 HAFC_1 -
17 Vsaw - V. saw filter
18 Vout O V. drive
19 EW_out O Parabola waveform (for sidepin correection)
20 Xray I X-ray detection (for protection) [Detection : H]
21 Ys I Not used
22 Cb_input I Cb (external) signal
23 Y_input I Y (external) signal
I Cr (external) signal
24 Cr_input
- 3.3V
25 DVcc_3.3V
I Chroma signal (for YC separation output)
26 V3in/Cin
27 EHT_in I Not used
28 V2in/Y I Y signal (for YC separation output)
REMOCON
REMOCON
RECEIVER
MAIN MI-COM /
VIDEO PROCESS /
IC702
S C L 1
DEF. PROCESS
MEMORY
S D A 1
S C L 0 S D A 0 S C L 0 S D A 0
IC5501
IC5001
MTS LATCH&
AV SW
TONE/VOL
Function
A F T 1
IC201
SCL0 SDA0
S C L 0 S D A 0 S C L 0
IC5201 TU001
3-LINE YC SEP. TUNER
Pin
I/O
Pin name
No.
29 YCD_GND - GND
30 Vin1 I Not used
31 ABCL I Current for automatic beam (brightness)/contrast limit
32 Monitor O Not used
- Black level detection filter
33 Black_Det
34 SVM_out O Y signal for scan velocity modulation
35 APL_Fil - Average picture level filter
36 APC_Fil - Automatc phase control filter
37 3.58MHz O Color sub carrier (3.58MHz) for 3-line digital comb filter [IC5201]
38 YC_Vcc_5V - 5V (for video process circuit)
39 R_out O R signal
40 G_out O G signal
41 B_out O B signal
42 RGB_Vcc_9V - 9V (for RGB process circuit)
I Not used
43 IK in
GND
44 TV_DGND -
45 uP_MPAGND - GND
46 uP_MPAVDD - 5V
47 MAIN_POWER O Power on/off switching control [Powen on : L]
48 HAZARD I B1 over cuurent / V. amplitude detection (for protect) [Defective : H]
49 SDAO I/O Data for Inter IC control bus (for various devices)
50 SCLO O Clock for Inter IC control bus (for various devices)
51 SDA1 I/O Data for Inter IC control bus (for main memory)
O AGC adjustment (for tuner) <S45 in Service menu>
52 AGC ADJUST
O Clock for Inter IC control bus (for main memory)
53 SCL1
O POWER / ON TIMER LED lndication [lighting : L]
54 LED
55 REMOCON I Remote control sensor input [No input : H]
56 COMPULINK I AV COMPULINK lll control [No input : H]
IC101
IF DET
S D A 0
S C L 0 S D A 0
IC502
D-A CONVERTER
[AV-36F704]
Function
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