Allegro MicroSystems, Inc. has announced two new full bridge drivers for automotive and industrial applications. Available with direct control (A89505) and pulse width modulationA89506) these devices integrate critical features to make system design easier by replacing mechanical relays with solid state drivers to improve performance and reliability. With built-in capabilities, including flexible interface logic, EMI reduction with programmable port drive, motor current feedback and multiple diagnostic features, these devices require very few external components and are available in a 4 × 4 mm QFN package, 36% more -small from comparable 5 × 5 mm devices.
The A89505 and A89506 are ideal for vehicle applications such as window and door operators, EV charger locks, electronic parking brakes and folding mirrors. Their solid-state design also makes them ideal for battery-powered applications that include brush DC motors, such as building automation and robotics, improving battery reliability and life while making the smaller design easier.
Both drivers include built-in current metering capabilities, eliminating the need for external current resistors and reducing the requirements for external components to just seven. Integrated diagnostics further eliminates the need for additional microprocessor programming and additional circuits. Designers can fit the functionality they need into smaller system prints, reducing material bills (BOM) and PCB sizes, while increasing productivity and improving the user experience.
The A89505 and A89506 are based on Allegro’s decades of experience in engine management. Both are capable of 50V absolutely maximum supply voltages and offer higher gate drive voltages at low VBB and better battery efficiency, allowing designers to define cheaper FETs. They even allow lower standby current to reduce overall battery load.
IN A89505 and A89506 gate drivers help provide better motor control than mechanical relays and reduce the need for external components. Programmable gate drive reduces EMI and transients caused by fast switching, and both drivers can adjust the gate current to better control the tilt speed of the external MOSFETs.
Both devices include flags for detecting the current limit, which are activated when the programmable current limit is reached. This function allows the vehicle’s electronic control unit (ECU) to detect pinching or stopping, with the possibility of overloading the engine in the event of ice or frost.
IN A89505 and A89506 Available in 4 × 4 mm low profile, 20-pin QFN package (suffix “ES”) and 20-pin eTSSOP (suffix “LP”), both with open thermal pad.
Full-bridge 50-V gate drivers optimized for automotive and industrial apps