HD66702 (LCD-II/E20)
(Dot Matrix Liquid Crystal Display Controller/Driver)
Description
The HD66702 LCD-II/E20 dot-matrix liquid crystal
display controller and driver LSI displays alphanu-
merics, Japanese kana characters, and symbols. It
can be configured to drive a dot-matrix liquid
crystal display under the control of a 4- or 8-bit
microprocessor. Since all the functions required for
driving a dot-matrix liquid crystal display are
internally provided on one chip, a minimal system
can be interfaced with this controller/driver.
A single LCD-II/E20 can display up to two 20-
character lines. However, with the addition of
HD44100 drivers, a maximum of up to two 40-
character lines can be displayed.
The low 3-V power supply of the LCD-II/E20 under
development is suitable for any portable battery-
driven product requiring low power dissipation.
• Programmable duty cycles
— 1/8 for one line of 5
×
7 dots with cursor
— 1/11 for one line of 5
×
10 dots with cursor
— 1/16 for two lines of 5
×
7 dots with cursor
• Maximum display characters
— One line
1/8 duty cycle, 20-char.
×
1-line (no exten-
sion), 28-char.
×
1-line (extended with one
HD44100R), 80-char.
×
1-line (max. exten-
sion with eight HD44100s). 1/11 duty cycle,
20-char.
×
1-line (no extension), 28-char.
×
1-line (extended with one HD44100R), 80-
char.
×
1-line (max. extension with eight
HD44100Rs)
— Two lines
1/16 duty cycle, 20-char.
×
2-line (no exten-
sion), 28-char.
×
2-line (extended with one
HD44100R), 40-char.
×
2-line (max. exten-
sion with eight HD44100Rs)
Wide range of instruction functions
— Display clear, cursor home, display on/off,
cursor on/off, display character blink, cursor
shift, display shift
Choice of power supply (V
CC
): 4.5 to 5.5 V
(standard), 2.7 to 5.5 V (low voltage)
Automatic reset circuit that initializes the
controller/driver after power on (standard ver-
sion only)
Independent LCD drive voltage driven off of the
logic power supply (V
CC
): 3.0 to 8.3 V
•
Features
• 5
×
7 and 5
×
10 dot matrix possible
• 80
×
8-bit display RAM (80 characters max.)
• 7,200-bit character generator ROM
— 160 character fonts (5
×
7 dot)
— 32 character fonts (5
×
10 dot)
• 64
×
8-bit character generator RAM
— 8 character fonts (5
×
7 dot)
— 4 character fonts (5
×
10 dot)
• 16-common
×
100-segment liquid crystal display
driver
•
•
•
HD66702
LCD-II Family Comparison
Item
Power supply voltage
Liquid crystal drive
voltage V
LCD
Maximum display
digits per chip
Display duty cycle
CGROM
1/4 bias
1/5 bias
LCD-II (HD44780U)
2.7 to 5.5 V
3.0 to 11 V
3.0 to 11 V
16 digits
(8 digits
×
2 lines)
1/8, 1/11, and 1/16
9,600 bits
(208 character fonts
for 5
×
8 dot and
32 character fonts
for 5
×
10 dot)
64 bytes
80 bytes
40
16
A
External
External resistor
or external clock
270 kHz ±30%
(59 to 110 Hz for 1/8 and
1/16 duty cycles; 43 to 80 Hz
for 1/11 duty cycle)
91 kΩ ±2% (5 V)
75 kΩ ±2% (3 V)
LCD-II/E20 (HD66702)
5 V ±10% (standard)
2.7 to 5.5 V (low voltage)
3.0 to 8.3 V
3.0 to 8.3 V
40 digits
(20 digits
×
2 lines)
1/8, 1/11, and 1/16
7,200 bits
(160 character fonts for
5
×
7 dot and
32 character fonts for
5
×
10 dot)
64 bytes
80 bytes
100
16
B
External
External resistor or external
clock
320 kHz ±30%
(69 to 128 Hz for 1/8 and
1/16 duty cycles; 50 to 93 Hz
for 1/11 duty cycle)
68 kΩ ±2% (5 V)
56 kΩ ±2% (3 V)
CGRAM
DDRAM
Segment signals
Common signals
Liquid crystal drive waveform
Ladder resistor for LCD
power supply
Clock source
R
f
oscillation frequency
(frame frequency)
R
f
resistance
Instructions
CPU bus timing
Package
Fully compatible within the LCD-II family
1 MHz
FP-80B, TFP-80, and 80-pin
bare chip (no package)
1 MHz
144-pin bare chip (no package)
and FP-144A
270
微控制器 MCU
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