Active OR’ing controller increases maximum voltage for power systems

The ZXGD3111N7 active OR-ing MOSFET controller from Diodes Incorporated is targeted at power systems that use redundancy to achieve high reliability in telecom, data centre and server applications and increases performance with a 200V maximum drain voltage. This increase in VDRAIN from the previously announced 40V ZXGD3108N8 allows this latest device to address requirements in 48V common rail systems where the outputs of two or more power supplies are OR’ed together in order to provide redundancy. In addition to its 200V rating, which is claimed to be twice that of its competitors, the device has a low turn-off threshold voltage with a tight tolerance of -5mV to -1mV. This improves stability under light load conditions when using low RDS(ON) MOSFETs, making this controller a class-leading solution that can deliver the highest efficiency and reliability over the entire load range. The device is designed to work with a FET to create an ideal diode that replaces the blocking diodes typically used in common rail designs. A 5A sink current capability allows fast discharge of the gates in the paralleled OR’ing MOSFETS and its quick <600ns turn-off specification avoids reverse current flow and any voltage drop on the common rail. The device claims to have an industry-leading standby power consumption of <50mW with a quiescent supply current of <1mA.