Accurate, Pre-RTL Temperature-Aware Design Using a Parameterized, Geometric Thermal Model

Abstract

Abstract-Preventing silicon chips from negative, even disastrous thermal hazards has become increasingly challenging these days; considering thermal effects early in the design cycle is thus required. To achieve this, an accurate yet fast temperature model together with an early-stage, thermally optimized, design flow are needed. In this paper, we present an improved block-based compact thermal model (HotSpot 4.0) that automatically achieves good accuracy even under extreme conditions. The model has been extensively validated with detailed finite-element thermal simulation tools. We also show that properly modeling package components and applying the right boundary conditions are crucial to making full-chip thermal models like HotSpot accurately resemble what happens in the real world. Ignoring or oversimplifying package components can lead to inaccurate temperature estimations and potential thermal hazards that are costly to fix in later designs stages. Such a full-chip and package thermal model can then be incorporated into a thermally optimized design flow where it acts as an efficient communication medium among computer architects, circuit designers and package designers in early microprocessor design stages, to achieve early and accurate design decisions and also faster design convergence. For example, the temperature-leakage interaction can be readily analyzed within such a design flow to predict potential thermal hazards such as thermal runaway. An example SoC design illustrates the importance of adopting such a thermally optimized design flow in early design stages.Index Terms-compact thermal model, early design stages, leakage, parameterized model, temperature, thermally optimized design flow.

BTI aware thermal management for reliable DVFS designs

“…Indeed, different workloads Consequently, a considerable temperature difference may be exhibited by the blocks/paths in a design, which may reach 20 o C [13]. In addition, operating frequency and voltage, which do not affect stress ratio [2], are the main players in determining the power consumption, thus the thermal profile of a design.…”

“…This information, together with the layout, feeds the HotSpot tool [13] that conducts a thermal analysis of each operating mode. The block diagram of the developed flow is shown in Fig.…”

“…6 that we have developed for the BTI degradation analysis of DVFS designs accounting for workload and actual thermal profiles, which are generated considering statistically probable workload and DTM constraints utilizing the HotSpot tool [13].…”

“…In order to properly account for these variabilities in lifetime estimation at design time, we propose a simulation framework for the BTI degradation analysis of DVFS designs accounting for workload and actual thermal profiles, which are generated considering statistically probable workload and dynamic thermal management (DTM) constraints by means of the HotSpot tool [13]. The proposed approach allows us to obtain the fined-grain stress ratio for every transistor in a circuit as well as a fine-grained temperature profile.…”

Physical Modeling and Simulation of Thermal Heating in Vertical Integrated Circuits

“…Almost all of the mathematical models used for thermal analysis, by many researchers and found in the literature, are only solving the heat equation as in [4]- [17]. And the heat source in this heat equation is assumed to be given.…”