Cascoded semiconductor devices

[0033] Embodiments of the present invention propose a cascode transistor circuit having a main depletion mode transistor and a cascode MOSFET formed, the two transistors being packaged to form the cascode transistor circuit. The bias circuit is connected between the gate of the power transistor and the low supply line of the circuit. A biasing circuit is integrated into the transistor circuit for compensating the forward voltage of the body diode of the cascaded MOSFET. In the absence of a bias circuit, the Schottky gate is in parallel with the body diode of the cascode MOSFET. Because the forward voltages can be nearly equal, a larger current can flow through the Schottky gate.

[0034] The bias circuit intentionally increases the forward voltage of the Schottky gate for reverse current, so all the current will flow through the MOSFET body diode.

[0035] Therefore, the proposed cascode transistor circuit structure can enable reliable reverse operation of the cascode switch.