2242CKTC

Manufacturer Part Number2242CKTC
ManufacturerFairchild Semiconductor
2242CKTC datasheet
 


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Applications Discussion

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PRODUCT SPECIFICATION

Applications Discussion

The TMC2242C is well-suited to filtering digitized compos-
ite or component NTSC or PAL video. In Figure 14, the
TMC1175A 8-bit video A/D converter outputs, D
connected to the TMC2242C inputs, SI
minimize noise and any chance of electrostatic damage,
inputs SI
should be grounded. Controls RND
3-0
100 and SO
is forced high to effect 8-bit rounding. SO
1
TCO, and DEC are forced low, whereas INT and SO
forced high. (Setting SO
high and TCO low selects
0
unsigned binary format at the input and output data ports,
eliminating the need for external MSB inverters.)
TTL Clock
27.000 MHz (D1)
28.636 MHz (NTSC D2)
2 uH
2 uH
Composite
300 pF
510 pF
Video
75 Ohm
300 pF
65-2242C-12
Figure 12. Decimating Oversampled Video With a Low Cost 8-bit A/D
TCO = 0 RND = 100 SO(3:0) = 0011 DEC = 0 INT = 1
TMC2242C
SO 15-6
SI 11-0
12
13.500 MHz (D1)
14.318 MHz (NTSC D2)
Note: Data buses are unsigned binary.
Figure 13. Interpolating Digital Video Signals before Reconstruction
TCO = 0 RND = 110 SO(3:0) = 0011 DEC = 0 INT = 0
12
In Figure 15, the TMC2242C drives a fast D/A converter to
reconstruct analog composite video. The TMC3003 10-bit
digital-to-analog converter inputs, D
TMC2242C outputs SO
, are
7-0
RND
controls are set to 110 for rounded 10-bit interpola-
2-0
, respectively. To
11-4
tion operation.
are set to
2-0
,
3-2
are
0
TMC1175A
VIN
8-bit A/D
8
75 Ohm
D 7-0
AGND
27.000 MHz (D1)
28.636 MHz (NTSC D2)
TMC3003
10-bit D/A
I OUT
10
D 9-0
AGND
27.000 MHz (D1)
28.636 MHz (NTSC D2)
TMC2242C
are connected to the
9-0
, respectively. The TMC2242C
15-6
TMC2242C
SI 11-4
8
SO 15-8
13.500 MHz (D1)
14.318 MHz (NTSC D2)
TTL Clock
27.000 MHz (D1)
28.636 MHz (NTSC D2)
2 uH
2 uH
Composite
510 pF
300 pF
75 Ohm
Video
300 pF
75 Ohm
65-2242C-13