Overvoltage protection and short-circuit withstanding for gallium nitride devices
AssigneeTexas Instruments Incorporated
InventorSandeep R. Bahl
Life of this patent
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Abstract
Disclosed examples include methods, integrated circuits and switch circuits including a driver circuit and a silicon transistor or other current source circuit coupled with a gallium nitride or other high electron mobility first transistor, where the driver operatives in a first mode to deliver a control voltage signal to the first transistor, and in a second mode in response to a detected overvoltage condition associated with the first transistor to control the current source circuit to conduct a sink current from the first transistor to affect a control voltage to at least partially turn on the first transistor.
Claims21
A circuit, comprising:
- a first transistor, including a first drain terminal coupled with a first circuit node, a first source terminal, and a first control terminal;
- a current source circuit coupled between the first source terminal and a second circuit node;
- and
- a driver circuit operative in a first mode to deliver a first control voltage signal to the first control terminal, and in a second mode in response to a detected overvoltage condition associated with the first transistor to control the current source circuit to conduct a sink current from the first source terminal to the second circuit node to affect a control voltage between the first source terminal and the first control terminal to at least partially turn on the first transistor.
A method of operating a switch circuit, the switch circuit including a first transistor connected to a first circuit node, and a current source connected between the first transistor and a second circuit node, the method comprising:
- in a first mode, delivering a first control voltage signal to the first transistor according to a drive signal;
- in the first mode, controlling the current source to provide a low impedance between the first transistor and the second circuit node;
- in a second mode, in response to detection of an overvoltage condition associated with the first transistor, controlling the current source to conduct a sink current from the first transistor to the second circuit node to at least partially turn on the first transistor.
An integrated circuit to control a switch circuit, the integrated circuit comprising:
- a first pad to electrically couple with a first source terminal of a first transistor of the switch circuit;
- a second pad to deliver a first control voltage signal to a first control terminal of the first transistor;
- an overvoltage sense circuit to deliver an overvoltage detection signal in response to detection of an overvoltage condition associated with the first transistor;
- and
- a driver circuit operative in a first mode to deliver the first control voltage signal to the second pad to control the first transistor, and in a second mode in response to the overvoltage detection signal to control a current source circuit to conduct a sink current from the first source terminal to affect a control voltage between the first pad and the second pad to at least partially turn on the first transistor.
Dependencies are inferred from the claim text.