Performance Comparison of Quasi-Delay-Insensitive Asynchronous Adders
Pith reviewed 2026-05-24 16:41 UTC · model grok-4.3
The pith
A comparison of quasi-delay-insensitive adders in 32/28nm CMOS points to architectures suitable for low power, energy, and area.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
QDI adders of various architectures were realized in 32/28nm CMOS and their design metrics compared to identify suitable options for low power/energy and reduced area.
What carries the argument
Quasi-delay-insensitive (QDI) adder architectures implemented in 32/28nm CMOS
Load-bearing premise
The QDI adders were implemented and simulated under equivalent conditions in the 32/28nm CMOS process.
What would settle it
A new set of simulations in the same 32/28nm process that changes which architectures appear best for power and area would falsify the results.
Figures
read the original abstract
In this technical note, we provide a comparison of the design metrics of various quasi-delay-insensitive (QDI) asynchronous adders, where the adders correspond to diverse architectures. QDI adders are robust, and the objective of this technical note is to point to those QDI adders which are suitable for low power/energy and less area. This information could be valuable for a resource-constrained low power VLSI design scenario. Non-QDI adders are excluded from the comparison since they are not robust although they may have optimized design metrics. All the QDI adders were realized using a 32/28nm CMOS process.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper is a technical note providing an empirical side-by-side comparison of design metrics (power, energy, area, delay) for multiple quasi-delay-insensitive (QDI) asynchronous adder architectures, all realized in the same 32/28nm CMOS process. Non-QDI adders are excluded. The goal is to identify which QDI adders are suitable for low-power/energy and reduced-area resource-constrained VLSI designs.
Significance. If the reported metrics reflect intrinsic architectural differences, the note supplies practical empirical guidance for selecting robust QDI adders in low-power scenarios. The work consists of an empirical side-by-side measurement of existing designs rather than new theory or proofs; its value is therefore conditional on the fairness of the implementation conditions.
major comments (1)
- [Abstract] Abstract: The central claim that the comparison identifies QDI adders 'suitable for low power/energy and less area' requires that the reported metrics reflect architectural differences. However, the statement that 'All the QDI adders were realized using a 32/28nm CMOS process' supplies no evidence (identical synthesis scripts, constraint files, place-and-route flows, or verification of equal design effort) that implementations were performed under strictly equivalent conditions. This is load-bearing for the ranking and recommendation.
Simulated Author's Rebuttal
We thank the referee for the constructive feedback on our technical note. The single major comment is addressed point-by-point below. We will incorporate revisions to strengthen the description of implementation conditions.
read point-by-point responses
-
Referee: [Abstract] Abstract: The central claim that the comparison identifies QDI adders 'suitable for low power/energy and less area' requires that the reported metrics reflect architectural differences. However, the statement that 'All the QDI adders were realized using a 32/28nm CMOS process' supplies no evidence (identical synthesis scripts, constraint files, place-and-route flows, or verification of equal design effort) that implementations were performed under strictly equivalent conditions. This is load-bearing for the ranking and recommendation.
Authors: We agree that explicit documentation of equivalent implementation conditions is necessary to support the architectural comparison. All designs were realized in the identical 32/28 nm CMOS process using the same standard-cell library and commercial EDA tools; however, the manuscript does not currently detail the synthesis scripts, timing constraints, or place-and-route settings. We will revise the paper by adding a new subsection (likely in Section II or III) that describes the common design flow, including the synthesis constraints, optimization directives, and verification steps applied uniformly to every adder. The abstract will also be updated to reference this methodology section. revision: yes
Circularity Check
No circularity: empirical comparison of existing designs
full rationale
The manuscript is a side-by-side empirical measurement of pre-existing QDI adder architectures realized in a common 32/28 nm process. No equations, fitted parameters, predictions derived from fits, self-citations used as load-bearing uniqueness theorems, or ansatzes are present in the provided text. The central claim rests on reported area/power/delay metrics rather than any derivation that reduces to its own inputs by construction. The noted concern about synthesis equivalence is a question of experimental control, not circularity in a claimed derivation chain.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption QDI adders are robust while non-QDI adders are not
Reference graph
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discussion (0)
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