Description
The HD66724/HD66725, dot-matrix graphics LCD controller and driver LSI incorporating a key scan function up to a 4-by-8 key matrix, display characters such as alphanumerics, katakana, hiragana and symbols as well as graphics such as kanji and pictograms. They can be configured to drive a dot-matrix liquid crystal display and control key scan functions under the control of the microprocessor connected via the clock-synchronized serial or 4/8-bit bus.

Features
• Control and drive of a character and graphics LCD with built-in key scan functions
• Three 12- (16-) character lines, 72 (96) -by-24 dot graphics, and 144 (192) segments
• 48 (64) grayscale segments
• Control up to a 4 × 8 (32 key) matrix key scan.
• 3 general ports built-in
• Low-power operation support:
    - Vcc = 1.8 to 5.5 V (low voltage)
    - VLCD = 3.0 to 6.5 V (liquid crystal drive voltage)
    - Single, double or triple booster for liquid crystal drive voltage
    - Contrast adjuster and voltage followers to decrease direct current flow in the LCD drive bleederresistors
    - Wake-up feature using key scan interrupt
    - Programmable drive duty ratios and bias values displayed on LCD
• Clock-synchronized serial interface
• 4-/8-bit bus interface capability (except when key scan circuit is used)
• 80 × 8-bit display data RAM (80 characters max)
• 20,736-bit (6 × 8 dots : 432 characters) character generator ROM
• 384 × 8-bit (64 characters) character generator RAM
• 96 × 2-bit (192 segment-icons and marks max) segment RAM
• 72- (96-) segment × 26-common-signal liquid crystal display driver
• Programmable display sizes and duty ratios
• Vertical and horizontal smooth scrolls
• Vertical double-height display
• Selectable CGROM memory bank (max. 432 fonts)
• Wide range of instruction functions:
    - Clear display, display on/off control, icon and mark control, character blink, black-white reversed blinking cursor, return home, cursor on/off, black-white reversed raster-row
• No wait time for instruction execution and RAM access (zero instruction)
• Internal oscillation (with external or built-in resistor) hardware reset
• Shift change of segment and common driver
• Slim chip with bumps for chip-on-glass (COG) mounting, and tape carrier package (TCP)