STE2002_06 ST Microelectronics, Inc., STE2002_06 Datasheet - Page 11

• Manufacturer Part Number: STE2002_06
• Description: 81 x 128 Single-chip LCD Controller/driver
• Manufacturer: ST Microelectronics, Inc.

STE2002
2.6
Temperature coefficient
As the viscosity, and therefore the contrast, of the LCD are subject to change with
temperature, there's the need to vary the LCD Voltage with temperature. The STE2002
provides the possibility to change the VLCD in a linear fashion against temperature with
eight different Temperature Coefficient selectable through the T2, T1 and T0 bits. Only four
of them are available with basic instruction set (TC1 & TC0 Bits).
Table 5.
Table 6.
Figure 4.
Finally, the V
Name
V
TC0
TC1
TC2
TC3
TC4
TC5
TC6
TC7
A
Name
LCD
TC0
TC2
TC3
TC6
0
00h 01h 02h 03h 04h 05h ….
Temperature coefficients
Temperature coefficients
LCD voltage
LCD
voltage at a given (T) temperature can be calculated as:
B
PRS = [0;0]
TC2
0
0
0
0
1
1
1
1
A
0
+ B
7Ch 7Dh 7Eh
TC1
0
0
1
1
V
LCD
7Fh 00h 01h 02h
TC1
(T) = V
A
0
0
1
1
0
0
1
1
1
03h 04h
LCD
PRS = [0;1]
o · [1 + (T-To) · TC]
05h ….
TC0
0
1
0
1
TC0
7Ch
0
1
0
1
0
1
0
1
7Dh 7Eh 7Fh
00h 01h 02h 03h 04h
A
2
-0.35 · 10
-1.05· 10
-1.05· 10
-1.75· 10
-0.7 · 10
-1.4 · 10
-2.1 · 10
-0.7 · 10
-2.1 · 10
-0.0· 10
-0.0· 10
-2.3· 10
Value
Value
PRS = [1;0]
05h
-3
-3
-3
-3
-3
-3
-3
-3
-3
-3
-3
-3
Circuit description
….
7Ch
7Dh 7Eh 7Fh
1/ °C
1/ °C
Unit
1/°C
1/°C
1/°C
1/°C
1/°C
1/°C
1/°C
Unit
1/°C
1/°C
1/°C
V
O
11/61