SILICONIX, represented in Australia by Braemac , has released n-channel MOSFETs that combine a 3.4V threshold voltage with on-resistance as low as 2.7mW. The 10 MOSFETs are available in 40V and 60V versions and are intended for use in high-temperature, high-current applications with inductive loads in the automotive, industrial and fixed telecom industries such as high-side switches, motor drives and 12V boardnets.
When MOSFETs operate in high-temperature, high-current environments, they can turn on spontaneously if their threshold voltage starts to approach 0V. One solution has been to add a negative voltage driver to the circuit, but this leads to increased circuit size, cost and complexity. Using a device with a high threshold voltage causes an undesirable increase in on-resistance.
The new MOSFETs use high-density silicon technology that allows the same device to deliver both low on-resistance and a high threshold voltage that avoids the problem of spontaneous turn-on in automotive, industrial and other applications involving high temperatures and high levels of current.
They are available in the DPAK, D2PAK, and PowerPAK SO-8 packages.