L9908TR [STMicroelectronics]

L9908 is a gate driver unit (GDU) for controlling 6 N-channel FETs for brushless motors in automotive applications.

Each one of the 3 half bridge drivers channels (HS/LS couples) can be independently configured allowing different load driving and is able to withstand -14 V to 95 V excursion on motor`s pins.

Through 6 dedicated parallel inputs the pre-driver stages can be controlled independently supporting duty cycle operations from 0% to 100% and allowing to implement all kinds of electric motor control strategy. A dedicated combination of regulators, charge pumps and bootstrap circuits allows L9908 to be suitable to operate in passenger, commercial or hybrid vehicles.

Safe operation of half bridges is ensured by shoot-through diagnosis, dead-time, short to battery, short to ground and open load detection plus a real time phase voltage monitoring.

L9908 is equipped with 3 independent high accuracy current monitor channels with SPI-configurable input differential voltage ranges for ground referenced current measurements, with 5 V/3.3 V output dynamic range compatibility.

L9908 implements diagnostics on external and internal supply, ground level, internal temperature.

A 32-bit out of frame SPI-slave interface is implemented for communication up to 10 MHz between L9908 and uC. SPI communication is safe-guarded by 5-bit CRC, 1bit frame counter, frame length check and an SPI-configurable Window Watchdog.

• AEC-Q100 qualified
• Full ISO26262 compliant, ASIL-D systems ready
• VDH motor supply voltage range from 4.5 V to 75 V for working in single (12 V systems), double (24 V systems) and 48 V battery applications
• 3.3 V internal supply voltage generated from 5 V on VDD pin
• Digital I/O compatible to 3.3 V/5 V logics
• 6 separate N-channel FET pre-drivers:
  • dedicated source connection to each FET
  • the device can withstand -14 V to 95 V on motor connection pins
  • 0% to 100% duty cycle operation support
  • dedicated PWM input pin for each gate driver
• 3 differential high accuracy current monitors for ground referred current measurements:
  • ADC/DAC architecture
  • SPI adjustable Gain Factor and Output Offset
  • built-in error calibration
  • the device can withstand -14 V to 6 V on input sensing pins
  • SPI readable current measurement
  • 0 to 4.6 V DAC output dynamic range
• 3 real time phase voltage monitor channels:
  • SPI programmable phase voltage feedback;
  • SPI readable phase duty cycle measurement;
• 32-bit - 10 MHz SPI interface with 5-bit CRC and 1bit frame counter for internal setting, self-test and full diagnostics
• Protection and diagnostic:
  • SPI programmable VDS diagnostic and protection in on-state
  • SPI programmable Dead Time protection
  • SPI programmable Shoot-through diagnostic and protection
  • Open load, short to GND and short to battery diagnostic in off-state
  • Over-temperature diagnostic and protection with SPI programmable warning flag
  • SPI readable Tj measurement
  • Ground loss diagnostic
  • System clock monitoring
  • Power supply pins VDD, VDH, VBP over-voltage and under-voltage diagnostic
  • FET driver supply VPRE and VCP under-voltage and over-voltage diagnostic
  • SPI Window Watchdog
  • Fault status flag output