Automotive 3-Phase Isolator MOSFET Driver with Reverse Battery and Battery Disconnect Channels


Allegro ET EV 28 Package Image

The A89103 provides three independent gate drives that can disconnect a motor from its drive circuitry to allow secondary system to take over control. The device includes additional drivers for battery disconnect and reverse battery isolation.


Top Features

Typical Applications


The A89103 is an N-channel power MOSFET driver capable of controlling five MOSFETs to provide motor phase isolation and supply isolation in three phase BLDC applications. Three floating gate drive outputs maintain phase isolator power MOSFETs in the on-state over the full supply range with high phase-voltage and under High dv/dt on motor phase connection for 12 V and 48 V systems. Two additional floating gate drivers are provided to isolate the battery supply voltage during reverse battery or short circuit conditions.

The A89103 supports both source to source and drain to drain battery MOSFET isolation. An integrated charge pump regulator provides the above battery supply voltage necessary to maintain the power N-channel MOSFETs in the on-state continuously. The charge pump will maintain sufficient gate drive (>7.5 V) for battery voltages down to 4.5 V with 100 kΩ gate source resistors.

The five floating gate drives can be configured, monitored and controlled through the SPI interface. When not in use the A89103 can be placed into a low-power sleep mode. Undervoltage 

  • Five floating N-channel MOSFET drives
  • Maintains VGS with 100 kΩ gate-source resistors
  • Integrated charge pump controller
  • 4.5 to 85 V supply voltage operating range
  • Supports source-to-source and drain-to-drain battery MOSFET isolation
  • VCP and VGS undervoltage protection
  • 150°C ambient (165°C junction) continuous
  • Fully integrated diagnostics for safe motor phase and battery disconnect
  • Extensive programmable diagnostics    
  • Diagnostic verification
  • Automotive AEC-Q100 qualified

The A89103 is supplied in a 28-contact wettable-flank quad flat no-lead (QFN) package (suffix ET), and 28-contact wettable-flank QFN (suffix EV), both with exposed pads for enhanced thermal dissipation. They are lead (Pb) free, with 100% matte tin leadframe plating.

ET Package Documentation

EV Package Documentation

Part Number Specifications and Availability