Advantech TREK-674, Manual

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Low Battery Protection
When the system is ON, and
(1) The battery voltage (DC input) is lower than LOW_THRESHOLD (at T
6
)
(2) and this situation lasts for LOW_DELAY ,
, then the system will send Power Button signal to OS (at T
7
) to start the shutdown
process.
At this time (T7), the
LOW_HARD_DELAY is starting to countdown.
Once LOW_HARD__DELAY is over, the system power is removed abruptly.
LOW_DELAY
is ranged from 1 to 3600 seconds.
LOW_HARD_ DELAY is fixed with a value of 60 seconds.
Note:
Q1
: How is the low-battery event raised or canceled?
A1 : The minimum value on LOW_DELAY parameter is 1 second. If the voltage remains
lower than the LOW_THRESHOLD in the duration of LOW_DELAY, the low-battery
event will be raised and immediately send a power button press signal to OS.
During the duration of LOW_DELAY, if the battery voltage is back to be higher than
LOW_THRESHOLD, the LOW_DELAY will be reset to predetermined value and stop
count down.
Therefore, the LOW_DELAY parameter acts as a filter to prevent incorrect
low-battery-event from happening.
4.3.2 Power Management demo program
TREK V3 VPM Sample Code
TREK V3 VPM Sample Code is demonstration of vehicle power management (VPM).
System Menu

TREK V3 VPM Sample Code as below figure
T
6
T
7
T
8
System stays ON
Low Battery is
Detected Send Power
Button Signal
System OFF
LOW_HARD_DELAY LOW _DELAY