A fast symbolic SNR computation method and its Verilog-A implementation for Sigma-Delta modulator design optimizationd

作者：Zhang, Ailin; Shi, Guoyong^*

来源：Integration, the VLSI Journal, 2018, 60: 190-203.

DOI：10.1016/j.vlsi.2017.09.007

• Behavioral modeling and simulation
• Mixed-signal integrated circuit (IC) design
• Optimization
• Sigma-Delta modulator (SDM)
• Switched-capacitor (SC) circuit
• Symbolic computation
• Verilog-A

Sigma-Delta modulator (SDM) is a type of medium-speed but high-accuracy data converter. Signal-to-noise ratio (SNR) is one of its most critical design metrics. To enable automatic synthesis, fast SNR evaluation is of uttermost importance to accelerate the synthesis loop. In this paper a fast symbolic SNR computation method is proposed, which can automatically generate analytical SNR calculation formulas given a loop filter circuit design. Furthermore, Verilog-A implementation of this method is introduced, which demonstrates the feasibility of using the fast SNR computation method in a standard mixed-signal design automation environment. Application of the Verilog-A modules to SDM circuit optimization is demonstrated by invoking the build-in quasi-Newton optimizer in a Verilog-A tool and compared to the simulated annealing (SA) optimization. This work is an attempt of demonstration that a symbolic computation method can be integrated into a commercial mixed-signal design tool with good performance in behavioral synthesis. Utilization of the proposed method for behavioral Monte Carlo simulation in the Verilog-A environment was also found to be encouraging.

• 出版日期2018-1
• 单位上海交通大学