HD66727
(Low-Power Dot-Matrix Liquid Crystal Display Controller/Driver
with Key Scan Function)
Description
The HD66727, dot-matrix liquid crystal display controller and driver LSI incorporating a key scan
function, displays alphanumerics, katakana, hiragana, and symbols. It can be configured to drive a dot-
matrix liquid crystal display and control key scan functions under the control of an I
2
C bus or a clock-
synchronized serial microprocessor. A single HD66727 is capable of displaying up to four 12-character
lines, 40 segments, and 12 annunciators, and controlling up to a 4-by-8 key matrix, and driving three LED.
The HD66727 incorporates all the functions required for driving a dot-matrix liquid crystal display such as
display RAM, character generator, and liquid crystal drivers, and it also incorporates a booster for the LCD
power supply and key scan functions.
The HD66727 provides various functions to reduce the power consumption of an LCD system such as low-
voltage operation of 2.4V or less, a booster for generating a maximum of triple LCD drive voltage from the
supplied voltage, and voltage-followers for decreasing the direct current flow in the LCD drive bleeder-
resistors. Combining these hardware functions with software functions such as standby and sleep modes
allows a fine power control. The HD66727, with the above functions, is suitable for any portable battery-
driven product requiring long-term driving capabilities and small size.
Features
•
•
•
•
Control and drive of a dot-matrix LCD with built-in key scan functions
Four 12-character lines, 40 segments, and 12 annunciators
Control of up to a 4
×
8-key matrix, 3 LED ports and 3 general ports
Low-power operation support:
2.4 to 5.5V (low voltage)
Double or triple booster for liquid crystal drive voltage
Contrast adjuster and voltage followers for decreasing the direct current flow in the LCD drive
bleeder-resistors
Standby mode and sleep mode
Displays up to 12 static annunciators
•
I
2
C bus or clock-synchronized serial interface
•
60
×
8-bit display data RAM (60 characters max)
1
HITACHI [ HITACHI SEMICONDUCTOR ]
