ROHM has developed dual MOSFETs that combine two 100V chips in a single package – ideal for fan motor drives applied in communication base stations and industrial equipment. New five models have been added as part of the HP8KEx/HT8KEx (Nch+Nch) and HP8MEx (Nch+Pch) series.
Recent years have seen a shift to higher voltages from conventional 12V/24V to 48V systems in communication base stations and industrial equipment – intending to attain higher efficiency by decreasing current values. In these situations, switching MOSFETs requires a withstand voltage of 100V to account for voltage fluctuations, as 48V power supplies are also employed in the fan motors for cooling these applications. However, increasing the breakdown voltage raises ON resistance (RDS(on)) (which is in a trade-off relationship), leading to decreased efficiency – making it challenging to accomplish lower RDS(on) and higher breakdown voltage. Moreover, unlike multiple individual drive MOSFETs normally applied in fan motors, dual MOSFETs that integrate two chips in one package are increasingly being adopted to save space.
In response, the company has developed two new series combining Nch and Pch MOSFET chips utilising the latest processes. Both series attain the industry’s lowest RDS(on) by adopting new backside heat dissipation packages with excellent heat dissipation characteristics. As a result, RDS(on) is lowered by up to 56% compared with standard dual MOSFETs (19.6mOhm for the HSOP8 and 57mOhm for the HSMT8 Nch+Nch), contributing to greatly lower set power consumption. At the same time, combining two chips in a single package delivers greater space savings by decreasing area considerably. For example, replacing two single-chip TO-252 MOSFETs with one HSOP8 reduces footprint by 77%.
Typical applications include fan motors for communication base stations; fan motors for factory automation, and other industrial equipment; and fan motors for data centre servers, etc.