Datasheet

Functional Description
16
SLES099C—March 2007TVP5147PFP
f − Frequency − MHz
−1
0
1
2
3
4
5
6
7
01234567
Gain = 0
Gain = 2
Peak at
f = 2.89 MHz
Gain = 0.5
Gain = 1
Amplitude − dB
Figure 2−15. Peaking Filter Response, PAL Square Pixel Sampling
2.2.3.1 Color Transient Improvement
Color transient improvement (CTI) enhances horizontal color transients. The color difference signal transition
points are maintained, but the edges are enhanced for signals which have bandwidth-limited color
components.
2.3 Clock Circuits
An internal line-locked PLL generates the system and pixel clocks. A 14.318-MHz clock is required to drive
the PLL. This can be input to the TVP5147 decoder at the 1.8-V level on terminal 74 (XTAL1), or a crystal of
14.318-MHz fundamental resonant frequency can be connected across terminals 74 and 75 (XTAL2). If a
parallel resonant circuit is used as shown in Figure 2−16, then the external capacitors must have the following
relationship:
C
L1
= C
L2
= 2C
L
− C
STRAY
,
where C
STRAY
is the terminal capacitance with respect to ground. Figure 2−16 shows the reference clock
configurations. The TVP5147 decoder generates the DATACLK signal used for clocking data.
TVP5147
74
XTAL1
14.318-MHz
Crystal
75
XTAL2
TVP5147
74
XTAL1
75
XTAL2
C
L1
C
L2
14.318-MHz
Clock
Figure 2−16. Reference Clock Configurations