HD44780 Hitachi Semiconductor (acquired by Renesas), HD44780 Datasheet - Page 3

• Manufacturer Part Number: HD44780
• Description: Dot Matrix Liquid Crystal Display Controller/driver
• Manufacturer: Hitachi Semiconductor (acquired by Renesas)

HD44780U Block Diagram
RS
R/W
E
DB4 to
DB7
DB0 to
DB3
GND
V
CC
output
Input/
buffer
inter-
MPU
face
Reset
circuit
ACL
8
8
register (IR)
register
Instruction
Instruction
decoder
Busy
Data
(DR)
7
flag
Character
(CGRAM)
generator
64 bytes
OSC1 OSC2
RAM
Address
counter
CPG
5
V1
7
8
V2
Parallel/serial converter
80
data RAM
(DDRAM)
8
(CGROM)
Character
Display
generator
9,920 bits
attribute circuit
V3
ROM
7
8
8
8 bits
5
and
V4
7
register
generator
40-bit
V5
Timing
shift
controller
Cursor
blink
40
and
register
circuit
16-bit
40-bit
latch
shift
LCD drive
Common
Segment
selector
voltage
signal
signal
driver
driver
HD44780U
COM1 to
COM16
SEG1 to
SEG40
CL1
CL2
M
D
3