Abstract: A depletion mode MOSFET and resistor are fabricated as a silicon carbide (SiC) integrated circuit (IC). The SiC IC includes a first SiC layer doped to a first conductivity type and a second SiC layer overlaid on the first SiC layer and doped to a second conductivity type. The second SiC layer includes at least four more heavily doped regions of the second conductivity type, with two of such regions comprising MOSFET source and drain electrodes and two other of such regions comprising resistor electrodes. The second SiC layer includes an isolation trench between the MOSFET electrodes and the resistor electrodes. At least two electrically conductive contacts are provided as MOSFET electrode contacts, each being positioned over at least a portion of a respective MOSFET electrode and two other electrically conductive contacts are provided as resistor electrode contacts, each being positioned over at least a portion of a respective resistor electrode.

Abstract: A high temperature photocurrent detector circuit including a transimpedance amplifier having multiple stages of gain, and a driver amplifier which generates a driver current that is proportional to the photocurrent flowing through a photocurrent sensor. The voltage source utilizes source voltage wires to generate a supply current that is proportional to the driver current enabling the photocurrent detector circuit to operate as a two wire photocurrent detector circuit.

Abstract: A compact power circuit configured for circuit breaker applications includes, in one embodiment, a plurality of current transformers, each current transformer being coupled to a respective one of the phase lines of a power line to generate a current proportional to the current in the respective one of the phase lines. The circuit also includes a plurality of operational amplifiers, each of the operational amplifiers being coupled to a respective one of the current transformers. The operational amplifiers generate the phase signals v.sub.a, v.sub.b and v.sub.c respectively. A neutral phase signal Vn is generated by a current transformer coupled to the neutral phase line of the power line. A ground fault signal is generated from the vector sum of signals v.sub.a, v.sub.b, v.sub.c and V.sub.n.