Philips Semiconductors
Preliminary specification
PANorama-IC (PAN-IC)
FEATURES
•
Horizontal sample rate conversion in both zoom and
compress direction, with a sample rate conversion factor
between 0.5 and 2 (in 384 steps)
•
Dynamic sample rate conversion for panorama mode
display e.g. 4 : 3 material on a 16 : 9 display
•
Dynamic sample rate conversion for amaronap mode
display of e.g. 16 : 9 material on a 4 : 3 display
•
Operates with 1f
h
and 2f
h
•
Programmable via microcontroller SNERT
(Synchronous No parity Eight bit Receive Transmit) bus.
GENERAL DESCRIPTION
SAA4995WP
The PAN-IC is an add-on IC to be used, for example,
between analog-to-digital conversion and a serial (field)
memory. The device performs the following tasks:
•
Linear horizontal sample rate conversion in both zoom
and compress direction, with a sample rate conversion
factor between 0.5 and 2
•
Dynamic sample rate conversion for panorama mode
display of e.g. 4 : 3 material on a 16 : 9 display
•
Dynamic sample rate conversion for amaronap mode
display of e.g. 16 : 9 material on a 4 : 3 display.
The PAN-IC has the ability to increase the data rate from
the ADC to a maximum of twice the data rate at the output.
To achieve this a clock rate at twice the normal output
clock rate is needed to write data to the memory.
All actions to generate a lower data rate, produces disable
cycles in Write Enable (WE).
QUICK REFERENCE DATA
SYMBOL
V
DD
I
DD
f
CLK
T
amb
supply voltage
supply current
operating clock frequency
operating ambient temperature
PARAMETER
−
−
0
MIN.
4.5
5
110
−
−
TYP.
−
33
70
MAX.
5.5
V
mA
MHz
°C
UNIT
ORDERING INFORMATION
PACKAGE
TYPE NUMBER
NAME
SAA4995WP
PLCC44
DESCRIPTION
plastic leaded chip carrier; 44 leads
VERSION
SOT187-2
1997 Jun 10
2
Philips Semiconductors
Preliminary specification
PANorama-IC (PAN-IC)
SAA4995WP
6 VDD4
2 UI0
1 UI1
handbook, full pagewidth
5 CL16
4 VI0
3 VI1
44 YI0
43 YI1
42 YI2
41 YI3
WEI 7
TEST 8
SCANIN 9
VDD1 10
T0 11
GND1 12
T1 13
WEod 14
VDD2 15
GND2 16
WEO 17
40 YI4
39 YI5
38 YI6
37 YI7
36 VRST
35 SNCL
SAA4995WP
34 SDNA
33 VDD3
32 GND4
31 CLK
30 GND3
29 YO7
UO1 21
YO5 27
YO0 22
YO1 23
YO2 24
YO3 25
YO4 26
UO0 20
YO6 28
VO0 18
VO1 19
MGK175
Fig.2 Pin configuration.
FUNCTIONAL DESCRIPTION
The PAN-IC is an add-on IC to be used, for example,
between analog-to-digital conversion and a serial (field)
memory. The device performs the following tasks:
•
Linear horizontal sample rate conversion in both zoom
and compress direction, with a sample rate conversion
factor between 0.5 and 2
•
Dynamic sample rate conversion for panorama mode
display of e.g. 4 : 3 material on a 16 : 9 display
•
Dynamic sample rate conversion for amaronap mode
display of e.g. 16 : 9 material on a 4 : 3 display.
The PAN-IC has the ability to increase the data rate from
the ADC (maximum 16 MHz in a 16/32 MHz concept) to a
maximum of twice the data rate. For this, a 32 MHz clock
rate is needed to write to the memory. All actions to
generate a lower data rate produces disable cycles in write
enable.
In panorama and amaronap modes, the sample rate
conversion factor is modulated along the video line.
1997 Jun 10
5
In the centre of the line a high quality compression (e.g.
with a factor
4
⁄
3
) has to be made. Towards the sides of the
line, more and more expansion and compression
respectively is made. The sample rate conversion factor
over a line will have a bathtub shape, with parameters
illustrated in Fig.3:
•
X
0l
and X
0r
, where in-between a constant data rate is
maintained (area I) and starting points from where a
curve can be programmed for its 2nd derivative (in
areas II and V)
•
X
1l
and X
1r
, points from where a new curve can be
programmed for its 2nd derivative (for areas III and IV)
•
X
2l
corresponds to the first sample in the output data
stream, defined by start of WE
I
•
X
2r
corresponds to the last sample in the output data
stream, defined by the programmed number of samples
•
C
1
, which controls the second derivatives of the data
rate in areas II and V
•
C
2
, which controls the second derivatives of the data
rate in areas III and IV.
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