Controller IC raises efficiency of reverse discharge protection circuitry

Emulating an ideal diode, by driving a P-channel MOSFET, the DZDH0401DW controller provides the high-side rail isolation necessary for reverse current blocking, in systems up to 40V. The compact size and high performance capabilities of this arrangement mean that it is optimised for use in cordless power tools and autonomous household/garden appliances (such as smart vacuum cleaners and smart lawnmowers). It is also well-suited to other applications, including OR-ing rectifiers used in the hot-swappable and N+1 redundancy power supplies used in data centre servers.

By combining the DZDH0401DW with a low on-state resistance MOSFET, designers will be able to benefit from vastly reduced power dissipation, when compared to Schottky diode solutions, particularly in high power applications. This improved efficiency results in lower thermal management costs and increased system reliability. In this configuration, the DZDH0401DW detects when input power is disconnected, then drives the MOSFET into an OFF state, thereby isolating any return current path and maintaining system stability.

The complete reverse discharge protection solution consists of the controller, a MOSFET and two resistors. This simple and compact arrangement minimises design effort and provides a solution that is suitable for deployment in space constrained designs.

The device is available in a SOT363 package (with 2.15mm x 2.1mm x 1mm dimensions).