CXA2075M
Description of Operation
Analog RGB signals input from Pins 2, 3 and 4 are clamped in the clamping circuit and output from Pins 23,
22 and 21, respectively.
The matrix circuit performs operations on each input signal, generating luminance signal Y and color
difference signals R-Y and B-Y. The Y signal enters the delay line to adjust delay time with the chroma signal
C. Then, after addition of the CSYNC signal input from Pin 10, the Y signal is output from Pin 16.
A subcarrier input from Pin 6 is input to the phase shifter, where its phase is sfited 90°. Then, the subcarrier
is input to the modulators and modulated by the R-Y signal and the B-Y signal. The modulated subcarriers are
mixed, sent to the band-pass filter to eliminate higher harmonic components and finally output from Pin 15 as
the C signal. At the same time, Y and C signals are mixed and output from Pin 20 as the composite video
signal.
Burst Signal
The CXA2075M generates burst signals at the timing shown below according to the composite sync signal
input.
H synchronization
SYNC
IN
(TTL level)
C VIDEO
OUT
COUT
V synchronization
ODD
SYNC
IN
EVEN
tD (B) tW (B)
Burst signal
tD (B) tW (B)
ODD
C VIDEO
OUT
EVEN
Synchronizing signal
Burst signal
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