Functional Description
MEN Mikro Elektronik GmbH
26
20BC50R00 E1 – 2015-09-07
3.1.1
Ignition
Using the ignition pin, the start-up and shut-down of the BC50R can be controlled.
If the ignition pin (IGNITIONCON, KL15) is connected to the power input pin
(POWERCON_IN, KL30) via a switch or a controller, switching on and off of the
BC50R can be controlled without having to disconnect the power supply.
Figure 7.
Connection of power pins from PSU
When the ignition is turned on, the 12 V supply voltage is also switched on (see
Figure 8, Ignition behavior
). When the ignition is turned off, the input voltage is not
switched off at once but can be supplied for a user-defined time (shut-down delay)
so that the operating system of the BC50R can shut down in a controlled way.
Figure 8.
Ignition behavior
The shut-down delay can be set using a watchdog. If the ignition signal is disabled
and the watchdog is running, it is possible to reset the watchdog timer by software
using the WDOG_EN signal to avoid a power shutdown. If the watchdog is running
and the timer is not restarted, the box computer is forced into power down mode
after approximately 5 minutes.
DC/DC
Converter
CPU
12V
Box
PC
Ignition
(IGNITIONCON,
KL15)
Power
Input
(POWERCON_IN,
KL30)
GND
(POWERCON_GND,
KL31)
Power
Input
Ignition
12V
Definable
shut
‐
down
delay
