Ramprasath S
Sachin S. Sapatnekar
ABSTRACT
Well island generation and well tap placement pose an important challenge in automated analog/mixed-signal (AMS) layout. Well taps prevent latchup within a radius of influence in a well island, and must cover all devices. Automated AMS layout flows typically perform well island generation and tap insertion as a postprocessing step after placement. However, this step is intrusive and potentially alters the placement, resulting in increased area, wire length, and performance degradation. This work develops a graph-based optimization that integrates well island generation, well tap insertion, and placement. Its efficacy is demonstrated within a stochastic placement engine. Experimental results show that this approach generates better area, wire length and performance metrics than traditional methods, at the cost of a marginal runtime degradation.
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Index Terms
- Analog/Mixed-Signal Layout Optimization using Optimal Well Taps
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