ST innovates high-voltage transistor technology

SINGAPORE: STMicroelectronics has introduced a new family of power MOSFETs combining higher voltage capability, greater ruggedness, and lower losses than previous devices, which are well suited for use in high-efficiency power supplies for products such as LCD monitors, televisions and energy-saving lamp ballasts.

The STx7N95K3 family introduces a new 950V breakdown-voltage class for power MOSFETs. This new class benefits systems that minimize energy losses by operating at high voltages such as 400V or more. Compared to competing 900V devices, ST’s new 950V power MOSFETs have a larger safe-operating area delivering greater reliability.

Designers can also use a single 950V MOSFET to replace two-transistor circuits sometimes used to build high-voltage supplies, simplifying design, reducing size and lowering component count.

In addition, the STx7N95K3 family has a higher avalanche current rating than competing devices, which ensures greater resilience to surges above the breakdown voltage which cause the device to avalanche. The avalanche-current rating of 9A compares with around 1A for the nearest competing 900V devices.

As well as withstanding higher applied voltages, the STx7N95K3 family also minimizes conduction losses by achieving RDS(ON) of less than 1.35 Ohm. This represents a 30 percent reduction in RDS(ON) per device size compared to previous-generation MOSFETs, and allows designers to increase power density as well as improve efficiency.

At the same time, these new MOSFETs also deliver high switching performance by achieving low gate charge (QG) and low intrinsic capacitance, which allow designers to use higher switching frequencies, enabling the use of smaller components to further enhance efficiency and power density.

STx7N95K3 MOSFETs achieve these performance advantages by using ST’s latest-generation SuperMESH3™ technology. The devices introduced are offered in industry-standard packages including the STF7N95K3 in the TO-220FP package, the STP7N95K3 in standard TO-220, and the STW7N95K3 in TO-247.

The next available devices will be the 950V BVDSS STW25N95K3, STP13N95K3, STD5N95K3 and 1200V BVDSS STP6N120K3. ST will follow these devices with further new product introductions in 2009, including 850V, 950V, 1050V and 1200V ranges.

The STx7N95K3 family is in production, priced at $2.00 in quantities of 1,000 pieces.