ACX306AK
3. RGB Simultaneous Sampling
The horizontal driver samples R, G and B video signal simultaneously, which requires phase matching
between the R, G and B signals to prevent the horizontal resolution from deteriorating. Thus phase matching
by an external signal delay circuit is needed before applying the video signal to the LCD panel.
Two methods are applied for the delaying procedure: Sample-and-hold and Delay circuit. These two block
diagrams are as follows.
The ACX306AK has a right/left inversion function. The following phase relationship diagram indicates the
phase setting for right scan (RGT = high level). For left scan (RGT = low level), the phase setting should be
inverted for the B and G signals.
(1) Sample-and-hold (right scan)
BLUE
AC Amp
22
B
R
G
S/H
S/H
CKB
CKG
S/H
21 RED
S/H
AC Amp
AC Amp
CKR
CKG
S/H
20
GREEN
CKG
<Phase relationship of delaying sample-and-hold pulses> (right scan)
HCKn
CKB
CKR
CKG
(2) Delay element (right scan)
BLUE
AC Amp
22
B
R
G
Delay
Delay
Delay
21 RED
AC Amp
AC Amp
20
GREEN
– 20 –
SONY [ SONY CORPORATION ]
