cxa1779p Sony Electronics, cxa1779p Datasheet - Page 7

• Manufacturer Part Number: cxa1779p
• Description: Predriver For High Resolution Computer Displays
• Manufacturer: Sony Electronics

Description of Operation
1. Contrast control
2. Pedestal clamp and brightness control
3. Blanking additional function
The contrast for RGB IN (Pins 2, 5 and 8) input signals is adjusted using a DC externally input to the PIX
pin (Pin 12). In addition, the contrast for each RGB channel can be adjusted independently using a DC
externally input to the DRV pins (Pins 3, 6 and 9). (See Graphs 1 and 2.)
The pedestal clamp clamps the pedestal level when the CLP pin (Pin 14) is high. The RGB IN pin voltage at
the pedestal is approximately 3.2V when the pedestal is clamped. The CLP pin threshold level is 3V for V
and 1.5V for V
Using a DC externally input to the R, G and B BRT pins (Pins 26, 22 and 18), the brightness control
samples and holds the pedestal with the capacitance connected to the RGB SH pins (Pins 27, 23 and 19)
when the CLP pin (Pin 14) is high, thereby adjusting the pedestal level of the R, G and B channels. (See
Graph 3.)
Output is blanked when the BLK pin (Pin 16) is high. The BLK pin threshold level is 3V for V
V
blanking interval. (See Figs. 4 and 5.)
L
. See the Example of Input/Output Signals for output signal levels. The output signal is 0.3V during the
L
. (See Fig. 2.)
– 7 –
H
and 1.5V for
CXA1779P
H