CS4954-CQZR Cirrus Logic Inc, CS4954-CQZR Datasheet - Page 23

• Manufacturer Part Number: CS4954-CQZR
• Description: IC NTSC/PAL Digital Video Encoder
• Manufacturer: Cirrus Logic Inc
• Type: Video Encoderr

Specifications of CS4954-CQZR

• Voltage - Supply, Analog: 3.15 V ~ 5.25 V
• Voltage - Supply, Digital: 3.15 V ~ 5.25 V
• Mounting Type: Surface Mount
• Package / Case: 48-TQFP, 48-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: CDB4955A - EVALUATION BOARD FOR CS4955A
• Applications: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5.7
Since the subcarrier is synthesized from CLK, the
subcarrier frequency error will track the clock fre-
quency error. If the input clock has a tolerance of
200 ppm then the resulting subcarrier will also
have a tolerance of 200 ppm. Per the NTSC speci-
fication, the final subcarrier tolerance is ±10 Hz
which is approximately 3 ppm. Care must be taken
in selecting a suitable clock source.
In MPEG-2 system environments the clock is actu-
ally recovered from the data stream. In these cases
the recovered clock can be 27 MHz ±50 ppm or
±1350 Hz. It varies per television, but in many cas-
es given an MPEG-2 system clock of 27 MHz,
±1350 Hz, the resultant color subcarrier produced
will be outside of the television’s ability to com-
pensate and the chrominance information will not
be displayed (resulting in a black-and-white picture
only).
DS278F6
NTSC-M, NTSC-J
PAL-B, D, G, H, I, N 4.43361875 MHz 54131596
PAL-N (Argentina)
PAL-M
Address
0×00
0×01
0×04
0×05
0×10
0×11
0×12
0×13
0×14
System
Subcarrier Compensation
CONTROL_0
CONTROL_1
CONTROL_4
CONTROL_5
SC_SYNTH0
SC_SYNTH1
SC_SYNTH2
SC_SYNTH3
SC_AMP
Register
3.5795455 MHz 43E0F83E
Table 3.
3.582056 MHz
3.579611 MHz
Fsubcarrier
Table 4. Multi-standard Format Register Configurations
R.BT601
NTSC-M
1Ch
3Eh
F8h
E0h
ITU
01h
12h
07h
78h
43h
Value (hex)
43CDDFC7
43ED288D
R.BT601
NTSC-J
1Ch
3Eh
F8h
E0h
ITU
01h
10h
07h
78h
43h
NTSC-M
RS170A
1Ch
3Eh
F8h
E0h
The CS4954/5 is designed to provide automatic
compensation for an excessively inaccurate
MPEG-2 system clock. Sub-carrier compensation
is enabled through the XTAL bit of the
CONTROL_2 Register. When enabled, the
CS4954/5 will utilize a common quartz color burst
crystal (3.579545 MHz ± 50 ppm for NTSC) at-
tached to the XTAL_IN and XTAL_OUT pins to
automatically compare and compensate the color
subcarrier synthesis process.
5.8
The CS4954/5 is capable of NTSC Closed Caption
insertion on lines 21 and 284 independently.
Closed captioning is enabled for either one or both
lines via the CC_EN [1:0] Register bits and the
data to be inserted is also written into the four
Closed Caption Data registers. The CS4954/5,
when enabled, automatically generates the seven
cycles of clock run-in (32 times the line rate), does
start bit insertion (001), and finally does insertion
of the two data bytes per line. Data low at the video
outputs corresponds to 0 IRE and data high corre-
sponds to 50 IRE.
There are two independent 8-bit registers per line
(CC_21_1 & CC_21_2 for line 21 and CC_284_1
& CC_284_2 for line 284). Interrupts are also pro-
vided to simplify the handshake between the driver
software and the device. Typically the host writes
21h
16h
07h
78h
43h
B,D,G,H,I
Closed Caption Insertion
PAL-
41h
30h
07h
78h
15h
96h
15h
13h
54h
PAL-M
CDh
DFh
C7h
61h
12h
07h
78h
15h
43h
CS4954 CS4955
PAL-N
A1h
30h
07h
78h
15h
96h
15h
13h
54h
(Argent)
Comb.
PAL-N
EDh
8Ch
81h
30h
07h
78h
15h
28h
43h
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