CXA3572 Sony Corporation, CXA3572 Datasheet - Page 23

• Manufacturer Part Number: CXA3572
• Description: Driver/Timing Generator for Color LCD Panels
• Manufacturer: Sony Corporation

• Sample-and-hold circuit
•
This circuit performs time axis correction for the RGB output signals in order to support the RGB simultaneous
sampling systems of LCD panels.
RGT = H (Normal)
RGT = L (right/left inversion)
The sample-and-hold circuit performs sample and hold by receiving the SH1 to SH4 pulses from the TG
block. Since LCD panels perform color coding using an RGB delta arrangement, each horizontal line must be
compensated by 1.5 dots. This relationship is reversed during right/left inversion. This compensation and
other timing is also generated by the digital block. The sample-and-hold timing changes according to the
phase relationship with the HCK pulse, so the timing should be set to the SHS1 to SHS6 position in
accordance with the actual board.
In order to support the characteristics of LCD panels, the I/O characteristics are as shown in Fig. 1. The 1
gain transition point A voltage changes as shown in Fig. 2 by adjusting the serial bus register 1, and the 2
gain transition point B voltage changes as shown in Fig. 3 by adjusting 2.
correction
SH1
SH2
SH3
SH4
SH1
SH2
SH3
SH4
Output
G
R
B
Through
Through
SHS1
SHS1
C
C
B
A
B
A
A
S/H1
SH1
Through
Through
Fig. 1
SHS2
SHS2
C'
C'
A'
B'
A'
B'
B
S/H2
SH2
Input
Through
Through
SHS3
SHS3
S/H3
SH3
A
C
B
A
C
B
SH4
Through
Through
Output
SHS4
SHS4
C'
B'
A'
C'
B'
A'
S/H4
S/H4
S/H4
A
Through
Through
A'
SHS5
SHS5
Fig. 2
– 23 –
C
C
B
A
B
A
B
R
G
B
Input
B'
Through
Through
SHS6
SHS6
C'
C'
B'
A'
B'
A'
HCK1
Output
SH1: R signal SH pulse
SH2: G signal SH pulse
SH3: B signal SH pulse
SH4: RGB signal SH pulse
SHS1, 2, 3, 4, 5, 6:
A
A'
B
B'
C
C'
A
Fig. 3
B
B'
Input
Serial data settings
CXA3572R