Patent ID: 9705489
Date: 2017-07-11
CPC Classifications: H03K

Claim:
1. A cascode transistor circuit comprising: a drain output terminal; a source output terminal; a depletion-mode switch including a normally-on control terminal and a normally-on conduction channel; a normally-off switch including a normally-off control terminal and a normally-off conduction channel, wherein the normally-off control terminal is configured to receive a normally-off control signal, and wherein the normally-off conduction channel is connected in series with the normally-on conduction channel between the drain output terminal and the source output terminal; a controller including a controller output terminal configured to provide a normally-on control signal for the normally-on control terminal of the depletion-mode switch, wherein the normally-on control signal is controlled independent of the normally-off control signal; a negative voltage source configured to provide a negative voltage to the normally-on control terminal of the depletion-mode switch, wherein the negative voltage source includes a bootstrap circuit connected between the controller output terminal and the normally-on control terminal of the depletion-mode switch; and a feedback capacitance between the drain output terminal and a control node in a circuit path between the controller output terminal and the normally-on control terminal of the depletion-mode switch.