l99h01 STMicroelectronics, l99h01 Datasheet - Page 31

• Manufacturer Part Number: l99h01
• Description: Motor Bridge Driver For Automotive Applications
• Manufacturer: STMicroelectronics

L99H01
3.12
3.12.1
3.12.2
3.13
Thermal sensor interface / H-bridge switch-off input
The TS/ACT_OFF pin is configurable by SPI with the EXT_TS bit. This pin could be used as
temperature sensor interface for the H-bridge or external off for all gate drivers. The output
bias current ITS_bias is on for EN = high.
EXT_TS-bit = low (active off)
The TS/ACT_OFF input is used as a logic driver control input, without filter delay and
without latching the information.
Pulling the TS/ACT_OFF pin below the programmed threshold all gate drivers are
switched-off and the OT_EXT bit is set.
Increasing the voltage at TS/ACT_OFF pin above the programmed threshold the device
remains to the status set by DIR and PWM-pins and the OT_EXT bit is reseted.
The threshold is programmable by SPI with the registers EXTTH_5:0.
EXT_TS-bit = high (thermal sensor interface)
With the thermal sensor interface external diodes can be used to control the temperature of
the external H-bridge. When the diode forward voltage decreases below the reference
voltage for longer than the internal filter time (64 µs) the OT_EXT bit is set and the driver
switches in resistive low (see
In this mode the OT_EXT-status-bit has to be cleared to reactivate the gate drivers.
The threshold is programmable by SPI with the registers EXTTH_5:0.
Watchdog
The tasks of the watchdog is to monitor the microcontroller during normal operation within a
nominal trigger cycle of 60 ms. The microcontroller has to restard the watchdog timer by
sending the watchdog restart bit via SPI repeatedly within the watchdog time T
correct watchdog service is send from the microcontroller, all gate drivers switch in sink
condition and the watchdog time out bit (WDTO) is set. Once the watchdog times out, the
gate drivers can only be reactivated by sending a software reset.
Section 3.4: Resistive
Doc ID 15567 Rev 3
low).
WDTO
. If no
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