High-performance gate driver SBC enables safe, efficient BLDC motor control
The ATA6847 from Microchip works with external controller and power devices to provide a complete solution for brushless dc motor system control. The gate driver eval board suits motors drawing up to 35 A current.
The Microchip ATA6847 is a powerful three-phase motor driver system basis chip (SBC) for use in automotive and industrial brushless dc (BLDC) motor control systems.
Built on advanced silicon-on-insulator (SOI) technology, this highly integrated motor driver SBC, supplied in a compact QFN package, provides precise gate control, robust diagnostic capabilities, and safety-ready features.
The ATA6847 works alongside a microcontroller and six external NMOS transistors to enable independent gate-drive control for each MOSFET, allowing full 0% to 100% PWM duty cycle operation via dual charge pumps. This enables sensorless BLDC motors to operate at high efficiency, even during start/stop or crank pulse events.
The chip includes two precision current-sense amplifiers with configurable gain and output offset, plus advanced current limitation using an operational amplifier and DAC. The integrated back-EMF detection module enables sensorless motor control with motor neutral point emulation, eliminating the need for external position sensors.
Robust safety mechanisms such as cross-conduction protection, MOSFET voltage monitoring, dead-time control, and configurable fault filter/blanking times ensure safe and reliable operation under all conditions. Additional features include a window watchdog with cyclic wake-up and limp-home mode.
The ATA6847 complies with the requirements of the ISO 26262 ASIL B and IEC 61508 SIL 2 standards for applications which require functional safety.