Standard ICs
Segment-type LCD driver
BU9729K
The BU9729K is a driver for segmented liquid crystal displays, which enables connection with a microcomputer
through a serial interface. 4-bit common output and an internal power supply circuit for LCD drive make it possible to
configure a low-cost display system.
鈥?/div>
Applications car audio equipment, telephones
Movie projectors,
鈥?/div>
Features (8-bit length).
1) Serial interface
2) Display RAM: 72bits, internal (up to 72 segments
can be displayed).
3) Internal power supply circuit for liquid crystal drive.
4) Display duty: 1 / 4.
5) Low-voltage and low-current operation supported.
鈥?/div>
Block diagram
V
LCD
V
C
LCD Driver
Bias Circuit
V
DD
V
SS
SEG1
SD
SCK
C/D
CS
Serial
Interface
Address
Counter
Display Data RAM
(DD RAM)
LCD
Segment
Driver
18bits
SEG18
SEG2
Command / Data
Register
LCD
Common
Driver
4bits
COM1
COM2
COM3
COM4
Command
Decoder
Timing
Generator
Common
Counter
OSC1
OSC2
1
next