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Technical information
and start-up
BSC624-12V-B
6.4.2
Internal current supplies
Generally, the device can be supplied by HV as well as via pin 2
AUX
. For the full operational availability,
however, the 12.5 V / 2.5 A supply must be active. This supply starts automatically at a HV voltage of > 75 V.
Due to the greater output voltage, the 11.3 V / 1 A supply of pin 2
AUX
is deactivated automatically in order to
reduce the current consumption from the wiring system.
The 5V supply is guaranteed as soon as either pin 3
EN
or pin 13
PRO
are connected with pin 2
AUX
. For
safety reasons, the hardware-side self-retaining function (uC via Enable1) is deactivated at the software-side.
In order to guarantee an optional autarkic operation of the device, a 10.7 V / 0.1 A supply is implemented.
Thus, for instance, pin 3 EN can be activated via a connection with pin 2 AUX in the customer side connector,
by which means the device remains switched on at all times.
The 12.5V / 2.5A supply is also realised with the auto-commutation topology (analogous buck / boost
converter
).
This supply is galvanically isolated from the high voltage circuit and furthermore functions without
optocoupler.
In the boost mode, the drivers are initially supplied during the start-up by pin 2
AUX
.
All supply circuits are short-circuit proof.
The signal ground pin 1
GND
is galvanically isolated from the power ground
PGND
. Thereby, stray voltage
and/or ground loops are avoided.
