3. LCD Block

During EE, gamma conversion is carried out for the 10-bit RGB data which is input from the A/D conversion block of the CCD to the ASIC in order that the γ revised can be displayed on the video. The YUV of 640 x 480 is then transferred to the

SVRAM.

The data which has accumulated in the SDRAM is after D/A conversion is carried out by SDRAM control circuit inside the ASIC, makes Y/C signal, the data is sent to the LCD panel and displayed.

If the shutter button is pressed in this condition, the 10-bit data which is output from the A/D conversion block of the CCD is sent to the SDRAM (DMA transfer), and is displayed on the LCD as a freeze-frame image.

During playback, the JPEG image data which has accumulated in the compact flash card is converted to RGB signals. In the same way as for EE, the data is then sent to the SDRAM, after which D/A conversion is carried out inside the ASIC, and then the data is sent to the LCD panel and displayed.

The LCD driver is converted Y/C signals to RGB signals from ASIC, and these RGB signals and the control signal which is output by the LCD driver are used to drive the LCD panel. The RGB signals are 1H transposed so that no DC component is present in the LCD element, and the two horizontal shift register clocks drive the horizontal shift registers inside the LCD panel so that the 1H transposed RGB signals are applied to the LCD panel.

Because the LCD closes more as the difference in potential between the VCOM (common polar voltage: fixed at DC) and the R, G and B signals becomes greater, the display becomes darker; if the difference in potential is smaller, the element opens and the LCD become brighter. In addition, the brightness and contrast settings for the LCD can be varied by means of the serial data from the ASIC.

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