The challenges of implementing fine-grained power gating
The challenges of implementing fine-grained power gating
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实施细粒度功率门控的挑战
DOI：
10.1145/1785481.1785564
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
J. Huisken
中科院分区：
文献类型：
--
作者：
Anja Niedermeier;K. Svarstad;F. Bouwens;Jos Hulzink;J. Huisken
在数字系统中，尤其是在便携式设备中，功耗是一个至关重要的设计因素。由于技术的缩小，动态开关电源不再是功耗的唯一相关来源，因为漏电流引起的功耗增加。尽管功率门控是一种看似简单的降低泄漏功率的方法，但在设计中引入功率门控的含义必须详细分析。我们提出了一个广泛的分析细粒度的电源门控对整体功耗的影响。所提出的结果是基于分析的一个非常长的指令字（VLIW）处理器的数据路径中的电源门控的实际实施。所提取的功耗值清楚地表明，与先前出版物中发现的分析相反，功率门控的开销不是由开启功率域所需的能量确定的，而是由额外所需模块的能耗确定的。我们表明，对于盈亏平衡点的情况下，约2/3的能量开销是由隔离单元引起的，约1/3是由控制模块引起的，只有大约1%的能量用于打开电源域。
Power consumption in digital systems, especially in portable devices, is a crucial design factor. Due to downscaling of technology, dynamic switching power is not the only relevant source of power consumption anymore as power dissipation caused by leakage currents increases. Even though power gating is a seemingly simple method for reducing the leakage power, the implications of introducing power gating to a design have to be analyzed in detail. We present an extensive analysis of the impact of fine-grained power gating on the overall power consumption. The presented results are based on the analysis of an actual implementation of power gating in the datapath of a very long instruction word (VLIW) processor. The extracted power consumption values clearly demonstrate that the overhead of power gating is, in contrary to the analysis found in previous publication, not determined by the energy required to switch a power domain on. Rather, it is determined by the energy consumption of additionally required modules. We show that, for the break-even point case, about 2/3 of the energy overhead is caused by the isolation cells, about 1/3 by the control modules, and only roughly 1% by the energy to switch a power domain on.