Siemens TC35 - Manual (Page 28)

26
Startup
Before startup, the components required for
your application must be connected. The
SIM card must be inserted in a deenergized
state.
The TC35 Terminal is ready for operation
when supply voltage is applied and the
ignition line is activated. If the
recommended plug-in power supply unit is
used, the ignition line is already connected
to the supply voltage line, and the TC35
Terminal is thus immediately switched to
the active state. It starts the network search
and registers with network operator. Please
read the following conditions for switching
the Terminal on and off:
Switching
onTerminal
Simply applying supply voltage (+ to pin 1
and GND to pin 6) alone is not enough to
switch on the TC35 Terminal.
It can be switched on in two different ways:
Activation of the IGT_IN ignition signal
on the power supply connection
The switching regulator is switched on with
the IGT_IN=high signal. When the
switching regulator is switched on, VBAT is
generated as the operating voltage for the
GSM module. This still does not activate the
GSM module. Triggered by VBAT, a
transistor switch generates the IGT ignition
signal with a delay of approx. 100ms for the
GSM module. Only then is it switched on.
(It exits the POWER DOWN operating
state.)