AY0438-I Datasheet, PDF (1/11 Pages) Microchip Technology – 32-Segment CMOS LCD Driver

AY0438
32-Segment CMOS LCD Driver
FEATURES
• Drives up to 32 LCD segments of arbitrary config-
uration
• CMOS process for: wide supply voltage range,
low- power operation, high-noise immunity, wide
temperature range
• CMOS and TTL-compatible inputs
• Electrostatic discharge protection on all pins
• Cascadable
• On-chip oscillator
• Requires only three control lines
APPLICATIONS
• Industrial displays
• Consumer product displays
• Telecom product displays
• Automotive dashboard displays
DESCRIPTION
The AY0438 is a CMOS integrated device that drives a
liquid crystal display, usually under microprocessor
control. The part acts as a smart peripheral that drives
up to 32 LCD segments. It needs only three control
lines due to its serial input construction. It latches the
data to be displayed and relieves the microprocessor
from the task of generating the required waveforms.
The AY0438 can drive any standard or custom parallel
drive LCD display, whether it be field effect or dynamic
scattering; 7-, 9-, 14- or 16-segment characters; deci-
mals; leading + or -; or special symbols. Several
AY0438 devices can be cascaded. The AC frequency
of the LCD waveforms can either be supplied by the
user or generated by attaching a capacitor to the LCD
input, which controls the frequency of an internal oscil-
lator.
The AY0438 is available in 40-lead dual in-line plastic
and 44-lead PLCC packages. Unpackaged dice are
also available.
PIN CONFIGURATION
40-Lead Dual In-line
VDD
1
40
LOAD
2
39
SEG 32
3
38
SEG 31
4
37
SEG 30
5
36
SEG 29
6
35
SEG 28
7
34
SEG 27
8
33
SEG 26
9
32
SEG 25
10
31
SEG 24
11
30
SEG 23
12
29
SEG 22
13
28
SEG 21
14
27
SEG 20
15
26
SEG 19
16
25
SEG 18
17
24
SEG 17
18
23
SEG 16
19
22
SEG 15
20
21
CLOCK
SEG 1
SEG 2
SEG 3
VSS
DATA OUT
DATA IN
SEG 4
SEG 5
LCDΦ
BP
SEG 6
SEG 7
SEG 8
SEG 9
SEG 10
SEG 11
SEG 12
SEG 13
SEG 14
44 PLCC
SEG 29
SEG 28
SEG 27
SEG 26
SEG 25
SEG 24
SEG 23
SEG 22
SEG 21
SEG 20
SEG 19
7
39
8
38
9
37
10
36
11
35
12
13
AY0438
34
33
14
32
15
31
16
30
17
29
NC
DATA OUT
DATA IN
SEG 4
SEG 5
LCDΦ
BP
SEG 6
SEG 7
SEG 8
NC
© 1995 Microchip Technology Inc.
DS70010I-page 1