Philips L01.2E AB - Page 47

Circuit Description
EN 47L01.2E AB 9.
Figure 9-3
9.2.2 Mono
In mono sets, the signal goes via the SAW filter (position 1004
in case of QSS demodulation and 1003 in case of Intercarrier
demodulation), to the audio demodulator part of the UOC
IC7200. The audio output on pin 48 goes directly, via buffer
7943, to the audio amplifier (AN7523 at position 7902).
The volume level is controlled at this IC (pin 9) by a
‘VolumeMute’ control line from the microprocessor.
The audio signal from IC7902 is then sent to the speaker/
headphone output panel.
Figure 9-4
TUNER
V
BAT
AUDIO
12V
3.9V
3.3V
FM IF
BUFFER
VIDEO SOURCE
SELECTION
RF ANT.
FM ANT.
EXT. AUDIO
INPUT
7801
FM FMR
AUDIO SOURCE SELECTION
CONTROL
EXT. AUDIO OUT
7861
7831
7834
7835
7209
7210
7901
10
1000
0265
11
1
11
AGC
1200 : 1202
18
19
22
23
33
47 24
25
24
38
INT_CVBS
EXT_CVBS
40
42
16 17 15 30
68
I2C
50:53
EXT RGB/YUV INPUT
56:58
7330
EHT
7460
H
EW
V+
V-
7471
7602
7200
SIF
VIF
POWER
SUPPLY
CL 16532008_039.eps
220501
AUDIO
AMPL.
SAW
FILTER
SAW
FILTER
SOUND
IF
DEMOD.
AUDIO DECODING
AND
PROCESSING
SELECTION
MATR. SWITCH
VISION
IF
DEMOD.
NVM
VIDEO
AMPL.
HOR.
DEFL.
+
EW
VERT.
DEFL.
µP
VIDEO
PROCESSING
RGB/YUV
PROCESSING
SYNC
PROCESSING
SOUND
TRAP
VIDEO
SWITCH
EXT. VIDEO
INPUT
7802
TUNER
RF ANT.
EXT. AUDIO
OUTPUT
EXT. AUDIO
INPUT
7902
7941
7942
7943
10
1000
11
1
11
AGC
18
19
23
24
68
7602
AUDIO SWITCH
VOLUME MUTE
7200
48
9
SIF
VIF
FM IF
BUFFER
FM FMR
AVL
AUDIO
AMPL.
SMART
SND
SAW
FILTER
SAW
FILTER
SOUND
IF
DEMOD.
VISION
IF
DEMOD.
NVM
µP
CL 16532008_040.eps
220501
FM ANT.
0265
22