New automotive isolator MOSFET driver IC replaces mechanical relays and discrete driver circuits

Allegro MicroSystems has introduced a new N-Channel power MOSFET driver capable of isolating a three phase load by controlling the in-phase isolation MOSFETS. Their A6862 motor driver IC is intended for automotive systems that must meet Automotive Safety Integrity Level requirements. This new device was designed for electronic power steering systems, electric braking, and three-phase relay driver applications and is supplied with detailed safety documentation. In safety critical applications motor isolation is an essential requirement which is currently addressed with discrete circuitry or relays in most competitive solutions. Their A²-SIL products are designed with industry-leading, innovative features to help customers achieve the highest ASIL rating possible. The three-phase isolation driver is intended to replace a relay driven motor disconnect in automotive safety critical systems. It also provides the drive for reverse battery protection and battery isolation. The device has three independent floating gate drive outputs to maintain the power MOSFETs in the on state, or the off state, over the full supply range in the presence of high phase-voltage slew rates. This new generation offers the addition of a single input control, two independent activation inputs to put the device into a low power sleep mode, and added gate to source protection to further assist end users to achieve critical system safety goals.