NXP Semiconductors MC9S08LC60, Manual

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Interfacing an LCD to the MC9S08LC60, Rev. 0
LCD Module Overview
Freescale Semiconductor 4
1.3 LCD Glass Specification
When obtaining TN-type LCD glass for an application, several parameters should be considered. These
include:
• LCD operating voltage — Typical values for LCD glass operating voltage are 3 V or 5 V. The
operating voltage is the nominal voltage level threshold to power on a segment.
• Current consumption — The current consumption is related to the total segment area.
• View area — This is related to the size of the LCD glass.
• Driving mode — Duty cycle (1/2, 1/3, and 1/4) and bias (1/3)
• View angle —
3 o’clock, 6 o’clock, 9 o’clock, and 12 o’clock
• View mode —
Reflective, transmissive, and transflective
• Operating temperature — Varies
2 LCD Module Overview
2.1 LCD Module Power Supply Configuration
The LCD module provides several configurations for its power supply. The LCD module can be powered
via V
DD
or, alternatively, by an external LCD power supply connected to the V
LCD
pin (the V
LCD
voltage
range is 1.4 to 1.8 V). The LCD module power supply configuration is determined by the VSUPPLY[1:0]
bit field. A block diagram of the power supply architecture is shown in
Figure 2 . The designer must choose
from one of the power modes shown in Figure 2 . This decision will be based on application requirements.
Figure 2. LCD Module Power Supply Configuration Options
+
–
R1
R1
R1
— (~(LCDCPMS) and powersw3)
~(LCDCPMS)
~(LCDCPMS)
(BBYPASS
V
LL1
(~(BBYPASS)
VOLTAGE DIVIDER
BLOCK
V
LCD
V
DD
powersw1 —
— powersw2
V
LL1
V
LL2
V
LL3
CHARGE PUMP
and powersw3)
and powersw3)
VSUPPLY[1:0] powersw1 powersw2 powersw3
00 1 0 0
01 0 1 0
10 0 0 1
11 0 0 0