MEN BL70S, User Manual

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Functional Description
20BL70S00 E3

2018-06-11 Page 41
Ignition Behavior

When the ignition is turned on (voltage higher than 5.3 V), the 12 V supply voltage is
also switched on (see figure below).

When the ignition is turned off (voltage lower than 0.8 V), a power button event is
generated.

Shut-down with or without delay:
- 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 BL70S
can shut down in a controlled way.
- The ignition pin can also be permanently connected to the power input pin.
In this case the BL70S will start up as soon as the supply voltage is con-
nected and switch off as soon as the supply voltage is disconnected without
a delay for shutting down the operating system.

The behavior (e.g., reboot, shut down) can be set in the operating system.
Figure 8. Ignition behavior
Setting a Shut-Down Delay
The shut-down delay can be set using a watchdog signal. 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 BL70S is forced into power
down mode after approximately 5 minutes.
 See Table 30, SMB Register (
0x40) on page 63
Power Input
(POWERCON_IN)
Ignition
(IGNITIONCON)
12 V
Definable shut ‐
down delay