High voltage switch
AssigneeUnited Silicon Carbide, Inc.
InventorXueqing Li
Life of this patent
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Abstract
A high-voltage switching device is formed by: connecting a number of normally-on transistors, such as JFETs, in series with each other, where the drain of each transistor is connected to the source of the next; connecting the chain of normally-on transistors in series with a normally-off switch component, such as a MOSFET, where the drain of the normally-off switch component is connected to the source of the first transistor in the chain in the chain; and, for each transistor, connecting a voltage-clamping device, such as a diode, with the anode of the voltage-clamping device connected to the source of the transistor and the cathode of the voltage-clamping device connected to the gate of the next transistor in the chain.
Claims5
A high-voltage switch comprising:
- a switching device, the switching device being a normally-off semiconductor device having a gate terminal, a drain terminal, and a source terminal;
- a chain of transistors, the transistors being normally-on semiconductor devices each having a gate terminal, a drain terminal, and a source terminal, where transistors are connected in series drain-to-source, and where the source of the first transistor in the chain is connected to the drain of the switching device;
- for each transistor in the chain from the second transistor in the chain to the penultimate transistor in the chain, a clamping device associated with the transistor, where an anode of the clamping device is connected to the source of the transistor, and a cathode of the clamping device is connected to the gate of the next transistor in the chain;
- an additional clamping device associated with the second transistor in the chain, where an anode of the additional clamping device is connected to the source of the switching device, and a cathode of the additional clamping device is connected to the gate of the second transistor;
- and
- for each transistor in the chain from the second transistor in the chain to the last transistor in the chain, a load circuit comprising a resistor, the load circuit being connected between the drain of the transistor and the gate of the transistor,
- where the gate of the first transistor in the chain is connected to the source of the switching device.
Dependencies are inferred from the claim text.