Philips 42PF9945 Service Manual page 48

Circuit Descriptions, Abbreviation List, and IC Data Sheets
9.7
Synchronisation
9.7.1
Introduction
Through the chassis, the synchronisation is complicated
because the PDP display needs another number of pixel per
line (852) and lines per frame (480). Therefore, there is a
different sync flow for 1fH, 2fH, or 3fH inputs.
Sync and Clock Flow
EPROM
RGB
Y Pb Pr
CLK32P
HA50
VA50 VA
Picnic
9.7.2
Sync Flow 1fH Inputs
1fH Sync Signals
•
At the 1fH side, the HIP is detecting the incoming video
signal and provides a H_A / V_A (Horizontal / Vertical
Acquisition sync) pulse. This is the sync input for the FBX.
•
The flywheel of the PICNIC gives a 1fH sync H_REF_EXT
to the EBILD, together with the V_A pulse.
•
These are switched in the EBILD and sent to Eagle
(H_REF and V_REF).
•
The Eagle delivers new sync pulses HD_E and VD_E
converted to the new line and frame sequence of the PDP
3fH. The PDP displays in 50 or 60 Hz, 480 lines per field
and 852 samples per line.
•
The EBILD delivers sync pulses to the OTC for OSD and
TXT (VD-OTC and HD3-OTC). Note that the OSD has a
field freq of 50/60Hz.
1fH Clock Signals
•
The PICNIC delivers a 32 MHz clock (CLK32P) to the
EBILD synchronised with H pulses.
•
The EBILD switches this signals to the Eagle (CLK32I).
•
The Eagle delivers a clock signal for the FALCONIC and
the field memories.
•
The Eagle delivers a 64 MHz clock to the EBILD (CLK64).
H-SYNC-VGA (DVI)
V-SYNC-VGA (DVI)
TDA8601
SH95
Video
Matrix
YUV
SW
YUV
FM
FM
FM Falconic
Href_ext
Figure 9-11 Sync and clock flow
AD9883A
H-2FH-AD-OUT
V-2FH-AD-OUT
SYNCDET
A/D
CLK-2FH
XTAL
SOG (Y)
HREF_EXT
clock
C L
FM
32 MC
(lower lines)
Eagle
FM
(upper lines)
H/V
HREF jmp
SYNC
jmp
VREF
9.7.3
Sync Flow 2fH Inputs
2fH Sync Signals
•
The input signals do not come via the HIP and PICNIC, but
via the AD9883A. This AD converter delivers H and V sync
signals to the EBILD (H-2FH-AD-OUT and V-2FH-AD-
OUT).
•
These inputs are used for standard detection and H and V
shift.
•
The EBILD divides the pulses by two, and switches the H
and V syncs to the Eagle (H_ref and V_ref).
•
The Eagle delivers new sync pulses HD_E and VD_E
converted to the new line and frame sequence of the PDP
3fH. The PDP displays in 50 or 60 Hz, 480 lines per field
and 852 samples per line.
•
The EBILD delivers sync pulses to the OTC for OSD and
TXT (VD_OTC and HD3_OTC). Note that the OSD has a
field freq of 50/60Hz.
•
The PICNIC receives V_ref pulses as reference; it is free
running for horizontal sync.
2fH Clock Signals
•
The AD9883A gives his sample clock (CLK-2FH) to the
EBILD, this clock is synchronised with the incoming H
pulses.
•
The EBILD switches this pulse to the Eagle (CLK32I).
FTP1.1E
EPLD
EBIL D
Standard
Detection
H,V
shift
REFCLK
jmp
Clock
switch
VA
Sync control
VREF
HREF
CLK64 YUV
UV demux
Contrast
to
saturation
RGB
brighness
Contrast
R0..7 G0..7 B0..7
Reserve
HS- VS- CLK- DE-OUT
HD_E
VD_E
DS90C385
LVDS Transmitter
LVDS
Connector
PDP
CL 36532075_048.eps
9. EN 107
CLK-VID
1/3
OSD
insertion
A/D
RGBBL-OSD
OTC
101103