908E621_07 Datasheet, PDF (34/62 Pages) Freescale Semiconductor, Inc – Integrated Quad Half-Bridge and Triple High-Side with Embedded MCU and LIN for High End Mirror

FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
VDD
10k
H0PD
H0MS
VSUP
H0MS
H0F
H0EN
H0
H0EN
Current
Sense
Figure 18. General purpose / hall-effect sensor input (H0)
Current Coded Hallsensor Input
H0 is selected as “2 pin hallsensor input”, if the
corresponding H0MS bit in the H0/L0 Status and Control
Register (HLSCTL) is set. In this mode the terminal current to
GND is monitored by a special sense circuitry. Setting bit
H0EN in the H0/L0 Status and Control Register switches the
output to VSUP and enable the sense circuitry. The result of
the sense operation is given by the H0F flag. The flag is low
if the sensed current is higher than the sense current
threshold I_HSCT. In this configuration the HO terminal is
protected (current limitation) against short circuit to GND.
After switching on the hallport (H0EN = “1”) the hallsensor
needs some time to stabilize the output. In RUN mode the
software has to take care about waiting for a few µs (40)
before sensing the hallflags.
The hallport output current is sensed. In case of an
overcurrent (short to GND) the hallport overcurrent flag
(H0OCF) is set and the current is limited. For proper
operation of the current limitation an external capacitor
(>100nF) close to the H0 terminal is required.
VSUP
H0EN
H0F
Current
Sense
V
2 pin hall sensor
H0
>0.1uF
GND
908E621
34
Analog Integrated Circuit Device Data
Freescale Semiconductor