Philips EM5A P/M - Video: Feature Box 7 (50 Hz signals)

Circuit Descriptions and Abbreviation List
EN 125EM5A P/M 9.
9.8 Video: Feature Box 7 (50 Hz signals)
The objective for this chassis was, to reach a sharper picture
by means of a higher definition.
This is achieved via the so-called 'Pixel Plus' feature. So, what
exactly is Pixel Plus?
For the Pal/Multi region we can distinguish two situations: 50
Hz PAL signals or 60 Hz NTSC signals. This chapter describes
the 50 Hz situation and chapter 1.9 describes the 60 Hz
situation.
9.8.1 Introduction
The basic function of the Feature box (FBX) is picture
improvement, and depending on the version, several scan
conversion methods are possible. The PICNIC (SAA4978H) is
the central key component.
In the EM5A-chassis, the feature-box is integrated on the SSB.
In the Feature Box 7 (FBX7), a new IC is used, called the
'Eagle'. This IC does the following picture improvements:
• Horizontal: increases from 840 to 1680 pixels per line (the
number of pixels is doubled per line). This, by itself, does
not mean an improvement in definition however. To
achieve that, the new pixels are digitally processed inside
the Eagle with Luminance Transient Improvement (LTI)
and Peaking. This will give the new pixels extra picture
information, which results in steeper slopes and contrast
improvement at details.
• Vertical: increases from 625 lines (PAL) to 833 lines. Also,
those new lines are processed inside the Eagle with LTI
and Peaking, again resulting in lines with extra picture
information.
• The line frequency is fixed on 31250 Hz and the frame
frequency at 75 Hz (this will give no frame-flicker). In
addition, other modes, like 'Digital Scan' are still possible.
• The colour enhancement features of the TOPIC are done
by the Eagle.
9.8.2 Block Diagram
Figure 9-13 Block diagram FBX7
CL 26532041_074.eps
170402
IC 7713
SAA4978H
PICNIC
IC 7712
ALE
EN
ACTIVE
'HIGH'
ACTIVE
'HIGH'
.139
A0...A7
LATCH
IC
A8...A15
IC 7711
M27C512
64k PROM
D0...D7
ADC
HA
VA
FILTERS
IC 7714
MS81V04160
MEM1
WE IE
8UV
8Y
BUS C
IC 7718
SAA4992
FALCONIC
8UV
8Y
IC 7717
MEM 2
IC 7719
MEM 3
IC 7722
MEM 5
IC 7723
MEM 4
IC 7724
EAGLE
DAC
FILTERS
HD
VD
YUV_EAGLE
8UV
8Y
8UV
8Y
8UV
8Y
8UV
8Y
A0...A7
8UV
8Y
RE D
BUS D
DIG
SCAN
100Hz
HD
VD