31
1.2.7 KA7630 Secondary
power integrated circuit
2
Electric circuit analyses
2.1 Super single chip integrated circuit TDA9373
As a super large-scale decoding and microprocessing integrated circuit, TDA9373 is comprised of a
microprocessor, picture image intermediate frequency amplification, sound intermediate frequency
amplification, line and field scanning, dwarf signal processing, color decoding, sound filtering and
auto identification, luminance separation, high voltage tracking and over voltage protection. It
functions for I
2
C bus-mastering and automatic adjustment for transmeridional correction and dark
balance.
Table 1 lists the pin function and test data of TDA9373 as the reference for maintenance.
The data is to be tested under the mode of 49.75MHz, PAL B/G and cylindrical color card muting,
using a model FLUKE 79 instrument.
Table 1
Resistance to Ground
R
Pin Function
Working
voltage V
Forward Test
Back Test
1. STANDBY
0
36K
29K
2. SCL
3.5
15K
15K
3. SDA
3.2
15K
15K
4. VT
3.0
20K
20K
5. KEY
3.4
36K
30K
6. SYSTEM
4.4
15K
15K
7. MUTE
5.1
15K
15K
8. GND.MAG
0
Infinity
2.9M
9.
VSS
C/P
0
0
0
10.
BAND
3.3
14.5K
14K
11.
BAND
0
14.5K
14K
12.
VSSA
0
0
0
13.
SEC.PLL
2.3
6.4M
4.3M
14.
VP2
7.8
18K
18K
15.
DECD/G
5.0
31.9K
32K
16.
PH2.LF
2.9
6.4M
4.2M
17.
PH1.LF
3.9
6.4M
4.2M
18.
GND3
0
0
0
19.
DEC.BG
4.0
39.8K
40K
20.
EWD
0.7
63K
63K
21.
V.DRB
2.4
6.0M
4.0M
22.
V.BRA
2.4
6.0M
4.0M
23.
IF.IN1
1.9
37.5K
38K
24.
IF.IN2
1.9
37.5K
38K
25.
I.REF
3.85
38.8K
38.8K
26.
V.S.C.
3.8
6.3M
4.6M
27.
TUNER.AGC
1.7
4.9K
4.9K
28.
AU.DEEM
3.2
6.1M
3.6M
Circuit Explanation
Содержание HP-2999
Страница 12: ...11 7 Net Dimension 790mm 525mm 590mm Net Dimension Figure 1 ...
Страница 30: ...29 c PCB Diagram Circuit Diagram Figure 6 ...
Страница 44: ...43 15 Exploded View EXPLODED VIEW OF CABINET PARTS Model HP 2999 Exploded View ...
Страница 66: ...65 ...