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Spice AST

The spice_ast module defines the Abstract Syntax Tree (AST) structures for SPICE netlists. Each element of a SPICE circuit (components, sources, subcircuits, etc.) is represented as a class with relevant attributes.

Base Classes​

Ast​

Base class for all AST elements.

class Ast(BaseModel):
    pass

Component​

Base class for circuit components with name, connections, and features.

class Component(Ast):
    name: str
    connections: list[str]
    features: list[Feature]

Expression​

Represents expressions with referenced identifiers and source span.

class Expression(Ast):
    references: set[str]
    span: Span

Feature​

Represents a feature/parameter with name and value.

class Feature(Ast):
    name: str
    value: Expression

Lib​

Library declaration with path and optional arguments.

class Lib(Ast):
    path: Span
    argument: Optional[Span]

Include​

Include declaration with file path.

class Include(Ast):
    path: Span

Circuit Definition​

CircuitDef​

Complete circuit definition with name, libraries, includes, parameters, components, connections, and formal parameters.

class CircuitDef(Ast):
    name: str
    libs: list[Lib]
    includes: list[Include]
    parameters: list[Feature]
    components: list[Component]
    connections: list[str]
    formal_parameters: list[Feature]

Passive Components​

Resistor​

Resistor component with value and optional model.

class Resistor(Component):
    value: Expression
    model: Optional[str]

Capacitor​

Capacitor component with optional value and model.

class Capacitor(Component):
    value: Optional[Expression]
    model: Optional[str]

Inductor​

Inductor component with optional value and model.

class Inductor(Component):
    value: Optional[Expression]
    model: Optional[str]

CoupledInductors​

Coupled inductors component with coupling value.

class CoupledInductors(Component):
    value: Expression

Semiconductor Devices​

Diode​

Diode component with model name and on/off state.

class Diode(Component):
    model: str
    on: bool

Bjt​

Bipolar junction transistor with model and state.

class Bjt(Component):
    model: str
    on: bool

Mosfet​

MOSFET component with model and state.

class Mosfet(Component):
    model: str
    on: bool

Jfet​

JFET component with model, optional area, and state.

class Jfet(Component):
    model: str
    area: Optional[Expression]
    on: bool

Mesfet​

MESFET component with model, optional area, and state.

class Mesfet(Component):
    model: str
    area: Optional[Expression]
    on: bool

Sources​

VoltageSource​

Voltage source with DC, AC, distortion, and transient specifications.

class VoltageSource(Component):
    dc_value: Optional[Expression]
    ac_magnitude: Optional[Expression]
    ac_phase: Optional[Expression]
    distortion_f1: DistortionTerm
    distortion_f2: DistortionTerm
    transient_value: Optional[Expression]

CurrentSource​

Current source with DC, AC, distortion, and transient specifications.

class CurrentSource(Component):
    dc_value: Optional[Expression]
    ac_magnitude: Optional[Expression]
    ac_phase: Optional[Expression]
    distortion_f1: DistortionTerm
    distortion_f2: DistortionTerm
    transient_value: Optional[Expression]

DistortionTerm​

Distortion term with magnitude and phase components.

class DistortionTerm(BaseModel):
    magnitude: Optional[Expression]
    phase: Optional[Expression]

Controlled Sources​

Vcvs​

Voltage-controlled voltage source.

class Vcvs(Component):
    value: Expression

Vccs​

Voltage-controlled current source.

class Vccs(Component):
    value: Expression

Cccs​

Current-controlled current source with controlling voltage name.

class Cccs(Component):
    vnam: str
    value: Expression

Ccvs​

Current-controlled voltage source with controlling voltage name.

class Ccvs(Component):
    vnam: str
    value: Expression

Transmission Lines​

LosslessTransmissionLine​

Lossless transmission line component.

class LosslessTransmissionLine(Component):
    pass

LossyTransmissionLine​

Lossy transmission line with model.

class LossyTransmissionLine(Component):
    model: str

SingleLossyTransmissionLine​

Single lossy transmission line with model.

class SingleLossyTransmissionLine(Component):
    model: str

UniformRcLine​

Uniform RC line with model.

class UniformRcLine(Component):
    model: str

CoupledMulticonductorLine​

Coupled multiconductor line with model.

class CoupledMulticonductorLine(Component):
    model: str

Switches and Subcircuits​

SwitchVC​

Voltage-controlled switch with model and state.

class SwitchVC(Component):
    model: str
    on: bool

SwitchCC​

Current-controlled switch with controlling voltage, model, and state.

class SwitchCC(Component):
    vnam: str
    model: str
    on: bool

Subcircuit​

Subcircuit instance with parent reference.

class Subcircuit(Component):
    parent: str

Placeholders​

XSpiceCodeModel​

XSpice code model component (not yet implemented).

class XSpiceCodeModel(Component):
    pass

BehaviouralSource​

Behavioural source component (not yet implemented).

class BehaviouralSource(Component):
    pass

VerilogDevice​

Verilog device component (not yet implemented).

class VerilogDevice(Component):
    pass