BTS5562E Datasheet, PDF (31/45 Pages) Infineon Technologies AG – SPI Power Controller

SPOC - BTS5562E
Diagnosis
Current Sense Multiplexer
There is a current sense multiplexer implemented in the SPOC - BTS5562E that routes the sense current of the
selected channel to the diagnosis pin IS. The channel is selected via SPI register DCR.MUX. The sense current
also can be disabled by SPI register DCR.MUX. For details on timing of the current sense multiplexer, please refer
to Figure 16.
CS
DCR.MUX 110 000
001
110
I
IS
t
sIS (E N)
t
t
t
s IS (MUX )
dIS (MUX )
Figure 16 Timing of Current Sense Multiplexer
t
MuxTiming.emf
8.3
Switch Bypass Diagnosis
To detect short circuit to V_BB, there is a switch bypass monitor implemented. In case of short circuit between the
output pin OUT and V_BB in ON-state, the current will flow through the power transistor as well as through the short
circuit (bypass) with undefined ratio. As a result, the current sense signal will show lower values than expected by
the load current. In OFF-state, the output voltage will stay close to V_BB potential which means a small V_DS.
The switch bypass monitor compares the voltage V_DS across the power transistor of that channel which is selected
by the current sense multiplexer (DCR.MUX) with threshold V_DS(SB). The result of comparison can be read in SPI
register DCR.SBM.
Data Sheet
31
Rev. 1.0, 2008-05-15