Allegro MicroSystems Releases 50V Full-Bridge Gate Driver for Automotive and Industrial Applications

Allegro MicroSystems (hereinafter referred to as Allegro), a global leader in motion control and energy-saving system sensing technology and power semiconductor solutions, announced the launch of two new full-bridge gate drivers for automotive and industrial applications. These devices have direct control (A89505) and pulse width modulation (A89506) options, which can integrate key functions upward to simplify system design and replace mechanical relays with solid-state drivers to improve performance and reliability. With built-in functions such as flexible interface logic circuits, programmable gate drive to reduce EMI, motor current feedback and multiple diagnostic features, these devices require few external components and adopt 4x4mm QFN packages, which are 36% smaller than similar 5x5mm devices.

The A89505 and A89506 are ideal for applications such as window and door actuators, electric vehicle charger locks, electronic parking brakes, and folding mirrors. The solid-state design of these devices also makes them ideal for battery-powered applications that contain brushed DC motors, such as building automation and robotics, improving system reliability and battery life while enabling designs with a smaller footprint.

Both drivers include built-in current sensing, eliminating the need for external current sensing resistors and reducing the number of external components required to seven, while integrated diagnostics eliminate the need for additional microprocessor programming and other additional circuitry. Designers can integrate required functionality into a smaller system footprint, reducing bill of materials (BOM) and printed circuit board size while improving performance and enhancing the consumer experience.

The A89505 and A89506 build on Allegro's decades of motor control expertise. Both products offer an absolute maximum supply voltage of 50V, which allows for higher gate drive voltages at low VBB and higher efficiency when powered by batteries, allowing designers to use lower cost FETs. These devices also offer lower current consumption in standby mode to reduce overall battery load.

“As vehicles continue to move toward full electrification, designers are looking for motor drivers that can improve system performance and battery life without increasing system design size, including designers of IoT and industrial applications,” said Steve Lutz, director of Allegro’s motor driver business. “In addition to being 36% smaller than other drivers on the market, the A89505 and A89506 integrate more advanced features and functionality to help designers reduce overall PCB size and fit everything they need into a more compact module. Both drivers are easier to use and implement than relays or discrete systems, reducing power consumption while also improving overall reliability.”

More integrated features increase design flexibility

Compared to mechanical relays, the A89505 and A89506 gate drivers provide better motor control and reduce the number of external components required. The programmable gate drivers reduce EMI and transients caused by fast switching, and both drivers can adjust the gate current to better control the slew rate of the external MOSFET.

Both the A89505 and A89506 gate drivers include current limit detection flags that are triggered when the programmable current limit is reached. This feature allows the vehicle electronic control unit (ECU) to detect pinches or stalls and to overdrive the motor in icing or freezing conditions.

The A89505 and A89506 are available in a low-profile 4 × 4 mm, 20-contact QFN package (suffix “ES”) and a 20-lead eTSSOP (suffix “LP”), both with exposed thermal pads.