Overview

The LC74731W and LC74732W are on-screen display CMOS ICs that display characters and patterns on a TV screen under the control of a microcontroller. These ICs display 16 x 16-dot characters and up to 12 lines of text with 24 characters per line.

Features

• Text structure : 12 lines x 24 characters (Up to 288 characters)

• Character format : 16 x 16 dots Character display clock frequency : about 9 MHz

• Character sizes : Four sizes each in the horizontal and vertical directions with the size set in line units.

• Number of characters supported : LC74731W : 256 (internal) LC74732W : 512 (internal) Up to 8192 using an external ROM (for Japanese)

[Reference] JIS X0298 (1990) : 6877 characters JIS level 1 kanji : 2965 characters JIS level 2 kanji : 3388 characters Special characters : 524 characters

• Display start positions : 128 positions each in the horizontal and vertical directions

• Blinking, reverse video, reversed blinking, and character outlining : May be specified in individual character units.

• Blinking types : Two types with periods of about 1.0 and about 0.5 seconds.

• Blanking : The whole font area (16 16 dots) can be blanked in line units (Four types : no blanking, character size blanking, character plus outlining size blanking, and whole area up to adjacent character blanking)

• Line spacing control : Zero to seven scan lines, in line units

• Character color : Eight colors in character units (in internal synchronization mode) : 2 fsc and 4 fsc (Black, red, green, yellow, blue, magenta, cyan, and white)

• Character background color : Eight colors (in internal synchronization mode) : 2 fsc and 4 fsc (Black, red, green, yellow, blue, magenta, cyan, and transparent)

• Screen background color : Eight colors (in internal synchronization mode) : 2 fsc and 4 fsc (Black, red, green, yellow, blue, magenta, cyan, and white)

• External control inputs : Serial interface with an 8-bit data size.

• Built-in sync separator circuit

• Video outputs : NTSC, PAL, PALM, PALN, NTSC 4.43, and PAL 60 composite video signal outputs

• Supports Y/C input