UJ3N Normally-On JFET Transistors UnitedSiC / Qorvo UJ3N JFET Transistors are high-performance, SiC Normally-On Junction Gate Field-Effect Transistors with options ranging from 650V to 1700V. This series exhibits ultra-low on resistance (RDS(ON)), as low as 25mΩ, and low gate charge (QG), allowing for low conduction and reduced switching loss. The device's normally-on characteristics with low RDS(ON) at VGS = 0V are also ideal for current protection circuits without the need for active control. The UJ3N JFET transistors are also commonly used in series connection with a Si-MOSFET as robust 'Supercascodes,' giving all of the advantages of wide band-gap technology with very high operating voltages and easy gate drive.