Asynchronous circuit for detecting and correcting soft error and implementation method thereof

A method for detecting and correcting soft error in an asynchronous circuit, the method comprises the steps of:

• recording in a first recording means the status of a signal output by a calculation unit;
• recording in a second recording means the status of the signal output by the logic calculation unit with a delay the duration of which being longer than a pulse duration of a soft error;
• and
• comparing the recorded signals from the first and second recording means and transmitting a signal carrying information corresponding to one of a first status in which the compared signals are identical and a second status in which the compared signals are different, and
• for the first status:
• providing a request signal for a control unit of a next logic stage without any delay, and
• for the second status:
• recording the status of the signal output by the logic calculation unit in the first recording means a second time after another delay the duration of which is longer than the pulse duration of an error, and then sending a request signal to the control unit of the next logic stage with a delay of a duration twice as long as the pulse duration of a soft error.

A method for detecting and correcting multiple soft errors in an asynchronous circuit, the method comprises the steps of:

• recording in a first recording means the status of a signal output by a calculation unit;
• recording in a second recording means the status of the signal output by the logic calculation unit with a delay the duration of which being longer than a pulse duration of a soft error;
• and
• comparing the recorded signals from the first and second recording means and transmitting a signal carrying information corresponding to one of a first status in which the compared signals are identical and a second status in which the compared signals are different, and
• for the first status:
• providing a request signal for a control unit of a next logic stage without any delay, and
• for the second status:
• repeating in a loop until no soft error is detected, the following steps a), b) and c):
• a) recording in a first recording means (2A) the status of a signal (Din) output by a calculation unit (1);
• b) recording in a second recording means (2B) the status of the said signal (Din) output by the said logic calculation unit (1) with a delay the duration (DL) of which is longer than the pulse duration of a soft error (Derreur);
• c) comparing the recorded signals (Dout, Doutr) in a comparer circuit until the compared signals are identical indicating no soft error is detected, then transmitting request signal (Rout) to the control unit of the next logic stage (E2) with a delay of a duration equal to:
• (number of soft errors detected)*2*DL, where DL is a duration greater than the known duration of a soft error pulse.

An integrated circuit comprising:

• an asynchronous circuit with a micro-pipeline type instruction execution mode designed to detect and correct soft error in digital integrated circuits, the asynchronous circuit comprising:
• at least one logic stage, each of the at least one logic stage comprising:
• a logic calculation unit whose output terminal transmits an output signal;
• a first recording means a first input terminal of which being coupled to the output terminal of the logic calculation unit;
• and
• a control unit one of whose three output terminals transmits a first data capture signal applied to a second input terminal of the first recording means, the other two output terminals of the control unit being respectively coupled to an input terminal of a control unit of a previous logic stage, and to an input terminal of a control unit of a next logic stage by means of a delay line;
• and
• wherein the asynchronous circuit also comprises:
• a second recording means one of whose two input terminals is coupled to the output terminal of the logic calculation unit;
• means in the control unit for delaying the first data capture signal and providing a second data capture signal that is applied to the second recording means;
• a comparer circuit one of whose two input terminals is coupled to the output terminal of the first recording means and whose other input terminal is coupled to the output terminal of the second recording means, the comparer circuit supplying an output signal that indicates in a first status that no soft error is present and in a second status that a soft error is present;
• and
• a programmable delay line whose first input terminal is coupled to the output terminal of the comparer circuit, a second input terminal being coupled to the output terminal of the delay line via a first delayed path and a last input terminal is coupled to the output terminal of the delay line via a second non-delayed path.

An electronic device comprising:

• an asynchronous circuit designed to detect and correct soft error in digital integrated circuits, the asynchronous circuit comprising:
• a logic calculation unit including an output that transmits an output signal;
• a first recording means having a first input coupled to the output of the logic calculation unit;
• a second recording means having an input coupled to the output of the logic calculation unit;
• a first control unit having three outputs, a first output couples a first data capture signal to a second input of the first recording means, the other two outputs of the first control unit being respectively coupled to an input of a second control unit of a first logic stage, and to an input of a third control unit of a second logic stage by means of a first delay line;
• and
• means in the first control unit for delaying the first data capture signal and providing a second data capture signal that is applied to the second recording means;
• a comparer circuit having a first input coupled to an output of the first recording means and a second input coupled to an output of the second recording means, the comparer circuit supplying an output signal that indicates one of
• a no soft error is present, and
• a soft error is present;
• and
• a programmable delay line having a first input coupled to an output of the comparer circuit, a second input being coupled to the output of the first delay line via a first delayed path and a third input being coupled to the output of the first delay line via a second non-delayed path.