Simplified thermal model for electronic fuse

A control system for an electronic fuse (“eFuse”) in an electric circuit having a connected load, comprising:

• a current sensor configured to sense a measured current in the electric circuit as an electric current is supplied to the connected load;
• a processor;
• a computer storage medium (“memory”) connected to the processor and containing instructions;
• and
• an accumulator having an accumulator value that represents a total amount of thermal energy associated with the measured current, wherein execution of the instructions by the processor causes the processor to:
• determine a range of the measured current in response to:
• (i) the measured current being greater than a predetermined maximum current, or (ii) the accumulator value being greater than zero;
• linearly adjust the accumulator value when the range of the measured current is in a predetermined range and the accumulator value is greater than a calibrated threshold, the calibrated threshold being greater than about 95% of a maximum accumulator value;
• and
• command the eFuse to switch to an off/non-conducting state when the accumulator value reaches a predetermined shutoff limit, thereby interrupting a flow of the electric current to the connected load.

An electric circuit, comprising:

• a power supply;
• a load connected to the power supply via a transfer conductor;
• an electronic fuse (“eFuse”) connected to the power supply and the load;
• and
• a control system for the eFuse, comprising:
• a current sensor configured to sense a measured current in the electric circuit as an electric current is supplied to the connected load;
• a processor;
• a computer storage medium (“memory”) connected to the processor and containing instructions;
• and
• an accumulator having an accumulator value that represents a total amount of thermal energy associated with the measured current, wherein execution of the instructions by the processor causes the processor to:
• determine a range of the measured current in response to:
• (i) the measured current being greater than a predetermined maximum current, or (ii) the accumulator value being greater than zero;
• linearly adjust the accumulator value when the range of the measured current is in a predetermined range and the accumulator value is greater than a calibrated threshold, the calibrated threshold being greater than about 98% of a maximum accumulator value;
• and
• command the eFuse to switch to an off/non-conducting state when the accumulator value reaches a predetermined shutoff limit, thereby interrupting a flow of the electric current to the connected load.