Garmin GDU 370 Installation Manual page 83

7.4.5.1 Display Configuration Window:
Backlight Intensity: Can be set to Auto or Manual (this setting is also available in normal mode on the
Display Setup page).
Auto–Sets the backlight intensity (display brightness) based on the aircraft's instrument lighting bus
voltage.
Manual–Allows setting the display brightness by changing the Backlight Intensity (0-9) setting
found beside the 'Manual' setting.
Default Mode: Can be set to Auto or Manual (described above). This controls the backlight mode that
will be active each time the system is powered on.
7.4.5.2 Automatic Backlight Control Window (settings apply only to 'Auto'
setting):
Input Voltage–Displays the current lighting bus voltage
Backlight Level–Displays the current backlight level (0-100%)
Graph–Brightness is displayed as the vertical (Y) axis, and aircraft lighting bus voltage is displayed as the
horizontal (X) axis. The graph changes according to the auto backlight control settings, and the lighting
bus voltage.
Off Threshold–Sets the lighting bus threshold voltage. At the threshold voltage, the backlighting is
turned on per the Min Brightness setting. Below the threshold voltage, the backlighting defaults to a
Backlight Level of 100% . The' ±' setting controls the range that the Off Threshold voltage is in effect.
Default values are 2.9V & ±0.15V.
Min Brightness (Voltage and Percentage)–Sets the lower bus voltage required to turn the backlighting on
to the percentage of brightness set by the Min % setting. Default values are 3.0V and 10%.
Max Brightness (Voltage and Percentage)–Sets the upper bus voltage required to turn the backlighting on
to the percentage of brightness set by the Max % setting. Default values are 12.0V and 100%.
Input Type–Sets the aircraft lighting bus voltage for either 12 or 24V input to match the aircraft lighting
bus voltage.
Time Constant–Adjusts the speed (in seconds), that the brightness level responds to changes in the input
voltage level.
G3X Installation Manual – Software, Configuration, Databases, and XM Activation
190-01115-01
Page 7-9
Revision A