FEATURES AND BENEFITS
Three-phase bridge MOSFET driver
• Bootstrap gate drive for N-channel MOSFET bridge
• Cross-conduction protection with adjustable dead time
• Charge pump for low supply voltage operation
• Top-off charge pump for 100% PWM
• Programmable gate drive voltage and strength
• 5.5 to 50 V supply voltage operating range
• Integrated logic supply
• Logic level phase state outputs
• Three current sense amplifiers
• Programmable gain and offset with offset output
• SPI-compatible serial interface
• Bridge control by direct logic inputs or serial interface
• TTL compatible logic inputs
• Extensive programmable diagnostics
• Diagnostic verification
• Safety-assist features
• Automotive AEC-Q100 qualified
• A2-SIL™ product—device features for safety-critical systems

DESCRIPTION
The A4911 is an N-channel power MOSFET driver capable
of controlling MOSFETs connected in a three-phase bridge
arrangement and is specifically designed for automotive
applications with high-power inductive loads, such as BLDC
motors.
The A4911 is intended for automotive systems that must
meet ASIL requirements. In common with other Allegro
A2-SIL™ products, it incorporates features to complement
proper system design, allowing users to achieve up to ASIL D
system classification.
A unique charge pump regulator provides the supply for the
MOSFET gate drive for battery voltages down to 7 V and
allows the A4911 to operate with a reduced gate drive down
to 5.5 V. Gate drive voltage and strength are programmable
to help reduce EMC issues. A bootstrap capacitor is used to
provide the above-battery supply voltage required for N-channel
MOSFETs.
Full control over all six power MOSFETs in the three-phase
bridge is provided, allowing motors to be driven with block
commutation or sinusoidal excitation. The power MOSFETs are
protected from shoot-through by integrated crossover control
and optional programmable dead time.
Integrated diagnostics provide indication of multiple internal faults,
system faults, and power bridge faults, and can be configured to
protect the power MOSFETs under most short-circuit conditions.
For safety-critical systems, the integrated diagnostic operation can
be verified under control of the serial interface.
The serial interface is provided to alter programmable settings and
read back detailed diagnostic information.
The A4911 is supplied in a 48-terminal wettable flank QFN package
(suffix EV) and a 48-pin QFP package (suffix JP), both with exposed
thermal pad. These packages are lead (Pb) free with 100% matte-tin
leadframe plating