A behavioral signal path modeling methodology for qualitative insight in and efficient sizing of CMOS opamps

Anaconda: SimulationBased Synthesis of Analog Circuits Via Stochastic Pattern Search

“…Although fast, these techniques proved to be difficult to update, and rather inaccurate. Numerical search has been used with equation-based evaluators [6]- [8], and even combinatorial search over different circuit topologies [9], [10], but equation-based approaches remain brittle in the face of technology changes. Recent work here has focused on coercing the required equations into a form more amenable to optimization; [11] shows results from rendering the equations as posynomials, thus, creating a convex optimization problem solvable via geometric programming.…”

“…Symbolic analysis techniques, which have made significant strides of late [7], [8], [18]- [21] offer an automated path to obtaining some of these design equations. These techniques automatically derive reduced-order symbolic models of the linear transfer function of a circuit.…”

Efficient analog circuit synthesis with simultaneous yield and robustness optimization

“…The optimization is done stepwise, as can be seen in Fig. 5, where the solution is gradually narrowed by enforcing more and more constraints on the design [4]. The initial solvability space is narrowed by adding the following sequence of constraints to the design plan.…”

“…The approach results in a drastic reduction of the required CPU time, without sacrifying too much accuracy. It is based on the use of symbolic techniques to capture the behavior of a circuit in a declarative model [4]. Constraint statisfaction techniques implemented in the tool DON-ALD [5] are then used to derive an efficient sizing plan as well as an efficient yield estimation plan.…”

MAELSTROM: efficient simulation-based synthesis for custom analog cells

“…Although fast, these techniques proved to be difficult to update, and rather inaccurate. Numerical search has been used with equation-based evaluators [5], [6], [7], and even combinatorial search over different circuit topologies [8], [9], but equation-based approaches remain brittle in the face of technology changes. Hierarchical systems [10], [11], [12], [13] introduced compositional techniques to assemble equation-based subcircuits, but still faced the same update/accuracy difficulties.…”