Transistor short circuit protection
AssigneeTexas Instruments Incorporated
InventorsCetin Kaya, Nathan Richard Schemm, Yong Xie
Life of this patent
Estimating the term…
Abstract
A short circuit detection circuit includes a current terminal, a sense resistor, an amplifier, and a resistor-capacitor ladder. The sense resistor is coupled to the current terminal, and is configured to develop a sense voltage proportional to a current through the current terminal. The amplifier is coupled to the sense resistor, and is configured to generate a scaled current proportional to the sense voltage. The resistor-capacitor ladder is coupled to the amplifier, and is configured to generate a measurement voltage that represents a surface temperature rise due to the current through the current terminal.
Claims18
A short circuit detection circuit, comprising:
- a current terminal;
- a sense transistor including:
- a first current terminal coupled to the current terminal;
- and
- a second current terminal;
- a sense resistor including:
- a first terminal coupled to the second current terminal of the sense transistor;
- and
- a second terminal;
- an amplifier including:
- a first input coupled to the first terminal of the sense resistor;
- a second input coupled to the second terminal of the sense resistor;
- and
- an output;
- and
- a resistor-capacitor ladder circuit comprising:
- an input coupled to the output of the amplifier.
A short circuit detection circuit, comprising:
- a current terminal;
- a sense resistor coupled to the current terminal, and configured to develop a sense voltage proportional to a current through the current terminal;
- a sense transistor coupled to the current terminal and the sense resistor, and configured to pass a sense current to the sense resistor, wherein the sense current is a fraction of the current through the current terminal;
- an amplifier coupled to the sense resistor, and configured to generate a scaled current proportional to the sense voltage;
- and
- a resistor-capacitor ladder coupled to the amplifier, and configured to generate a measurement voltage that represents a surface temperature rise due to the current through the current terminal.
A circuit, comprising:
- a switching transistor including:
- a current terminal;
- and
- a control terminal;
- a sense transistor including:
- a first current terminal coupled to the current terminal of the switching transistor;
- a second current terminal;
- and
- a control terminal coupled to the control terminal of the switching transistor;
- a sense resistor, including:
- a first terminal coupled to the second current terminal of the sense transistor;
- and
- a second terminal;
- an amplifier including:
- a first input coupled to the first terminal of the sense resistor;
- a second input coupled to the second terminal of the sense resistor;
- and
- an output;
- and
- a resistor-capacitor ladder circuit comprising:
- an input coupled to the output of the amplifier.
Dependencies are inferred from the claim text.