Glitch detection of a DC voltage
AssigneeSTMicroelectronics (Rousset) SAS
InventorsNicolas Borrel, Jimmy Fort
Life of this patent
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Abstract
A circuit for detecting a glitch in power supply includes a detection circuit to detect the glitch in a DC supply voltage of the power supply when a magnitude in the glitch in a DC supply voltage of the power supply exceeds a detection threshold, wherein the detection threshold is a function of the DC supply voltage, and wherein the detection circuit comprises a low pass filter, a control circuit coupled to the low pass filter, and a current mirror circuit coupled to the control circuit having an output for providing a logic signal indicative of a detected glitch.
Claims24
A circuit for detecting a glitch in power supply, the circuit comprising:
- a detection circuit configured to detect the glitch in a DC supply voltage of the power supply when a magnitude in the glitch in a DC supply voltage of the power supply exceeds a detection threshold, wherein the detection threshold is a function of the DC supply voltage, wherein the detection circuit comprises a control circuit configured for providing a current proportional to a filtered voltage obtained by low-pass filtering of the DC supply voltage;
- and
- a current mirror circuit coupled to and distinct from the control circuit, the current mirror circuit having an output configured for providing a logic signal indicative of a detected glitch.
A circuit for detecting a glitch in power supply, the circuit comprising:
- a first low-pass filter configured to supply a filtered voltage coupled between a first terminal and a second terminal of the power supply providing a DC supply voltage;
- a detection circuit coupled to the first low-pass filter and configured to detect the glitch in the DC supply voltage when an amplitude in the glitch in a DC supply voltage of the power supply exceeds a detection threshold proportionally varying with the filtered voltage, wherein the detection circuit comprises:
- a first branch comprising a first transistor and a first current source;
- and
- a second branch comprising a first resistor, a second transistor mirror-assembled with the first transistor, and a second current source supplying a first current varying proportionally to the filtered voltage.
A method of detecting a glitch in power supply, the method comprising:
- detecting the glitch in a DC supply voltage across an entire power supply range using a detection circuit by
- setting a detection threshold that depends on the DC supply voltage;
- and
- identifying a glitch when a magnitude in the glitch in the DC supply voltage of the power supply exceeds the detection threshold;
- and
- at a first low-pass filter, filtering the DC supply voltage to generate a filtered voltage, wherein the detection threshold proportionally varies with the filtered voltage;
- having a detection circuit coupled to the first low-pass filter, the detection circuit comprising a control circuit and a current mirror circuit coupled to and distinct from the control circuit including:
- a first branch comprising a first transistor and a first current source;
- and
- a second branch comprising a first resistor, a second transistor mirror-assembled with the first transistor, and a second current source supplying a first current varying proportionally to the filtered voltage.
Dependencies are inferred from the claim text.