Radiation-Hardened Storage Circuit Using Temporal Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated circuits face errors and malfunctions due to single-event effects (SEEs) from high-energy radiation, which existing technologies struggle to mitigate effectively with reduced hardware complexity.
Innovation Solution
An electrical circuit design utilizing two redundant master-slave memories with a multiplexer and a combinatorial logic circuit, where temporal redundancy replaces hardware redundancy, allowing operation with a single combinatorial logic circuit and optimized clock frequencies to correct single-event transients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If redundant circuit designs (TMR) are used to protect against single-event effects, then reliability is improved, but device complexity increases
Solution Approach 1:
The patent employs periodic clocking sequences where the multiplexer switches between selecting the combinational logic circuit output and selecting the input memory element output at regular intervals. This periodic switching enables temporal redundancy without requiring permanent duplicate hardware, thereby maintaining reliability while reducing device complexity compared to continuous TMR designs
Solution Approach 2:
The patent changes the operational parameters by using a single combinational logic circuit instead of triple redundancy, and compensates by implementing temporal redundancy through clocked switching. The parameter change from spatial redundancy (TMR) to temporal redundancy (periodic switching) reduces hardware complexity while maintaining protection against single-event effects
2Device complexity
If temporal redundancy is used instead of hardware redundancy, then device complexity is reduced, but measurement precision of error detection may worsen
Solution Approach 1:
The patent implements feedback through the multiplexer that continuously monitors and switches between the current combinational logic output and the previously stored input memory element output. This feedback mechanism enables real-time error detection by comparing current and previous states, maintaining measurement precision while using temporal rather than hardware redundancy
Solution Approach 2:
The input memory element stores the previous output state in advance before the switching occurs. This preliminary action of pre-storing the previous state enables immediate comparison and error detection when the multiplexer switches, maintaining error detection precision without requiring additional hardware complexity
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an electric circuit with two redundant master/slave storage units, each of which has a master storage element and a slave storage element; a signal input, which is connected to an input of a first of the master storage elements and which is designed to connect to a combinatorial logic circuit; an output selection element, which is connected to a respective output of the slave storage elements on the input side; and two intermediate selection elements, each of which is connected to an output of the two master storage elements on the input side and to different slave storage elements on the output side. According to the invention, the electric circuit is equipped with a multiplexer and an input storage element, which are connected to the signal input on the input side. The multiplexer is additionally connected to an output of the input storage element on the input side and to an input of a second of the master storage elements on the output side. The circuit is designed such that a storage unit clock signal with a common storage unit clock frequency can be supplied to the master slave storage unit and the input storage element, and a switchover clock signal with a switchover clock frequency can be supplied to the multiplexer in order to switch the multiplexer on the input side.