Systems and methods for using a security circuit to monitor a voltage of an integrated circuit to counter security threats to the integrated circuit

An integrated circuit, comprising:

• a power supply terminal configured to receive a voltage;
• a core circuit configured to be powered by the voltage received by the power supply terminal, wherein the core circuit comprises
• a volatile memory configured to store data,
• a clock source configured to provide a clock signal at a selected frequency, wherein the selected frequency is one of a plurality of possible frequencies of the clock signal, and
• a processor configured to operate according to the clock signal at the selected frequency;
• a security circuit configured to reset the core circuit based on i) the selected frequency of the clock signal and ii) the voltage of the power supply terminal, wherein resetting the core circuit clears the data from the volatile memory;
• and
• a non-volatile memory configured to store a plurality of performance points, wherein each performance point associates one of a plurality of voltage ranges with one of the possible frequencies of the clock signal;
• wherein the security circuit resets the core circuit based on a performance point corresponding to the selected frequency of the clock signal.

A method comprising:

• receiving a voltage at a power supply terminal of an integrated circuit;
• generating, within the integrated circuit, a clock signal at a selected one of a plurality of possible frequencies, wherein each of the plurality of possible frequencies is associated with a different respective allowed voltage range;
• storing data in a volatile memory of the integrated circuit;
• processing the data according to the clock signal at the selected frequency;
• and
• clearing the data from the volatile memory based on a comparison between i) the respective allowed voltage range associated with the selected frequency of the clock signal and ii) the voltage received at the power supply terminal.