Intelligent character display and491gst-led, Power supply – Purdy AND491GST-LED User Manual
Page 2

Intelligent Character Display
AND491GST-LED
Purdy Electronics Corporation • 720 Palomar Avenue • Sunnyvale, CA 94085
3/3/08
Tel: 408.523.8200 • Fax: 408.733.1287 • [email protected] • www.purdyelectronics.com
2
Power Supply
The LCD panel is driven by the voltage V
DD
–V
O
, so you need
an adjustable V
O
for contrast control and temperature
compensation.
Power Supply Block Diagram
Block Diagram
Dimensional Outline
Connector Pin Assignment
Pin No.
Signal
Function
1
V
SS
0V
2
V
DD
5V
3
V
O
Contrast Adj.
4
RS
Register Select
5
R/W
Read/Write
6
E
Enable
7
DBO
Data Bit 0
8
DB1
Data Bit 1
9
DB2
Data Bit 2
10
DB3
Data Bit 3
11
DB4
Data Bit 4
12
DB5
Data Bit 5
13
DB6
Data Bit 6
14
DB7
Data Bit 7
15
A
LED Power
16
K
Led Power
Temperature Variations
Temperature
V
DD
–V
O
0°C
4.80
+25°C
4.50
+50°C
4.20
V
DD
V
O
GND
V
DD
– V
O
V
DD
– V
O
= LCD Drive Voltage
VR10 to 20 k
Ω
VR
V
DD
(+5V)