Philips 32PF9968/10 Service Manual page 33

Circuit Descriptions, Abbreviation List, and IC Data Sheets
Figure 7-4 52" PSU block diagram
7.3 DC/DC converters
On-board DC-DC converters convert the +12 V coming from
the PSU. Refer to Figure 7-5
PSU/iPB : +3V3STBY
To PSU/iPB
To PSU/iPB
To PSU/iPB
PSU/iPB : +12VS
DC_DC
TPS54386
PWP
DC_DC
TPS54386
PWP
DC_DC
ST1S10PH
L78M08CDT
Figure 7-5 DC DC converter block diagram
7.4 Front-End
Key components for the analogue tuner section (AP region)
are:
• UV1816E tuner
• K7257 video SAW filter
• K9362 audio SAW filter
• TDA9886T analogue IF demodulator.
For trouble shooting info, refer to paragraph 5.6.6 Trouble
Shooting Tuner section.
18490_214_090410.eps
for details.
+3V3STBY To MT539X
/ under 15mA
STBY
PWM dimming
Boost
+12Vdisp
To LCD Panel
/1000mA
+5V_Tuner
To Tuner
/ 0.17Amax
+5VS
10uH To IF Demodulator
/ 0.07Amax
10uH To MT539X, USB,
+5V_SW
HDMI
/ 0.771Amax
10uH +1V2_SW
To MT539X
/ 0.5Amax
To MT539X, GDDR3
10uH
+1V8_SW
/1.13Amax
To MT539X, HDMi
10uH +3V3_SW
MUX, Audio DAC,
/1.094Amax
2uH +1V0_SW To MT539X
/ 2.1Amax
+8V_SW
To MT539X
/ 12mAmax
18490_212_090409.eps
Table 7-1 Pin assignment analogue tuners
Pin number Description
1 RF AGC voltage
2 n.c.
3 I
4 SCL
5 SDA
6 n.c.
7 supply voltage
8 n.c.
9 fixed tuning voltage
10 n.c.
11 TV IF output
7.5 Video Processing
090410
The video processing is completely handled by the Mediatek
MT5392 video processor which features:
• Noise reduction
• Dynamic skin tone control
• White stretch
• Blue stretch
• Green enhancement
• Auto histogram
• Pixel Plus III / Perfect Pixel
• Active Backlight dimming
• Active contrast.
7.6 Audio Processing
In this chassis, the TDA8932BT Class D Power Amplifier is
implemented. For trouble shooting info, refer to paragraph
5.6.7 Trouble Shooting Sound section.
7.7 HDMI
7.7.1 Introduction
Note: Text below is an excerpt from the "HDMI Specification"
that is issued by the HDMI founders (see www.hdmi.org).
090409
The High-Definition Multimedia Interface is developed for
transmitting digital signals from audiovisual sources to
television sets, projectors and other video displays.
HDMI can carry high quality multi-channel audio data and can
carry all standard and high-definition consumer electronics
video formats. Content protection technology is available.
HDMI can also carry control and status information in both
directions.
HDMI is backward compatible with DVI (1.0). Compared with
DVI, HDMI offers extra:
YUV 4:4:4 (3 × 8-bit) or 4:2:2 (up to 2 × 12-bit), where DVI
•
offers only RGB 4:4:4 (3 × 8 bit).
• Digital audio in CD quality (16-bit, 32/44.1/48 kHz), higher
quality available (8 channels, 192 kHz).
• Remote control via CEC bus (Consumer Electronics
Control): allows user to control all HDMI devices with the
TV's remote control and menus.
• Smaller connector (SCART successor).
• Less cables: e.g. from 10 audio/9 video cables to 3 HDMI
cables.
7.7.2 Implementation
In this chassis, the main "Mediatek" Video processor MT5392
combines the HDMI functionality together with the 4:1 "Analog
Device" HDMI switch ADV3002.
LC9.1A LA
DC voltage (V)
3.3 - 4.5 (weak or no signal)
< 3.3 (strong signal)
2
C-bus address select 0
0 to 3.3
0 to 3.3
5 +0.5/−0.25 V
33
7. EN 33
2009-Apr-10