User manual

...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 773
www.energymicro.com
33 LCD - Liquid Crystal Display Driver
0
1 2 3 4
LCD
Driver
EFM32
Quick Facts
What?
The LCD driver can drive up to 8x36
segmented LCD directly. The LCD driver
consumes less than 900 nA in EM2. The
animation feature makes it possible to have
active animations without CPU intervention.
Why?
Segmented LCD displays are common way to
display information. The extreme low-power
LCD driver enables a lot of applications to
utilize an LCD display even in energy critical
systems.
How?
The low frequency clock signal, low-power
waveform, animation and blink capabilities
enable the LCD driver to run autonomously
in EM2 for long periods. Adding the flexible
frame rate setting, contrast control, and
different multiplexing modes make the
EFM32GG the optimal choice for battery-
driven systems with LCD panels.
33.1 Introduction
The LCD driver is capable of driving a segmented LCD display combination of: 1x40, 2x40, 3x40, 4x40,
6x38 or 8x36 segments. A voltage boost function enables it to provide the LCD display with higher voltage
than the supply voltage for the device. In addition, an animation feature can run custom animations on
the LCD display without any CPU intervention. The LCD driver can also remain active even in Energy
Mode 2 and provides a Frame Counter interrupt that can wake-up the device on a regular basis for
updating data.
33.2 Features
• Up to 8x 36 segments.
• Configurable multiplexing (1, 2, 3, 4, 6, 8)
• LCD supports the following COM/SEG combinations
• 1x40, 2x40, 3x40, 4x40, 6x38, 8x36
• Configurable bias/voltage levels settings
• Configurable clock source prescaler
• Configurable Framerate
• Segment lines can be enabled or disabled individually
• Blink capabilities
• Integrated animation functionality
• Available on SEG0-SEG7 or SEG8-SEG15
• Voltage boost capabilities
• Possible to run on external power
• Programmable contrast