BTS54040-LBF_15 Datasheet, PDF (30/67 Pages) Infineon Technologies AG – SPI Power Controller

BTS54040-LBF
Power Stages
6.4.3 Switching Inductive Loads
When switching OFF inductive loads with high-side switches, the voltage V_OUT drops below ground potential,
because the inductance intends to continue driving the current. To prevent the destruction of the device due to
overvoltage, there is a voltage clamp mechanism implemented which limits that negative output voltage to a
certain level (V_DS(CL) (Chapter 6.6)). See Figure 15 for details.Please refer also to Chapter 7.4. The maximum
allowed load inductance is limited.
6.4.4 Switching Channels in Parallel
In case of appearance of a short circuit with channels in parallel driving a single load, BTS54040-LBF output
stages are not synchronized in the restart event. When all channels connected to the same load are in temperature
limitation, the channel which has cooled down the fastest doesn't wait for the other ones to be cooled down as well
to restart. Thus, it is not recommended to use the device with channels in parallel.
Note: In case of parallel channel operation, short circuit robustness may be reduced and n_RSC1 is not guaranteed
any more.
6.5
External Driver Control
One external smart power driver can be driven by the BTS54040-LBF via the external driver control block. There
are two control outputs available: one output for controlling the input (EDO) and one output for diagnosis enable
input (EDD). The current sense output of the external smart power driver can be connected to the IS pin. For
details please refer to Chapter 10.
The external driver output signals can be used only with applied V_DD voltage. The output is internally pulled down.
The external driver can be activated via SPI bit OUT.OUTn with n = 5.
Note: The usable duty cycle range and diagnostic timings depend on the external driver’s characteristics.
Data Sheet
30
Rev. 2.1, 2014-12-05