Struct BjtRoot 

pub struct BjtRoot {
    pub model: GummelPoonModel,
    pub is_pnp: bool,
    /* private fields */
}

BJT as a single-port WDF root (like TriodeRoot for tubes).

Vbe is set externally as a control parameter (from the base signal). The collector-emitter path is the WDF port. This enables:

• Standard WDF tree processing for BJT stages
• K-method table generation (2D: b_tree × Vbe)
• Blockwise decomposition of BJT cascades (303 ladder)

Uses the Gummel-Poon model for the I-V characteristic.

Fields

model: GummelPoonModel

is_pnp: bool

Implementations

impl BjtRoot

pub fn new(model: GummelPoonModel, is_pnp: bool) -> BjtRoot

pub fn new_with_v_max( model: GummelPoonModel, is_pnp: bool, v_max: f64, ) -> BjtRoot

pub fn initial_prev_v(&self) -> f64

Get the initial Vce warm-start (for diagnostics and testing).

pub fn set_initial_prev_v(&mut self, vce: f64)

Set the initial Vce warm-start from an init { } hint.

Called once at compile time. On reset(), prev_v is restored to this value, giving the NR solver an asymmetric starting point that can kick free-running oscillators (e.g. BJT astable multivibrators) out of the symmetric DC fixed point.

pub fn reset(&mut self)

Restore prev_v to the compile-time initial value.

Called by WdfStage::reset() for Bjt roots so that DAW resets return to the hint-specified asymmetric state rather than to 0.0.

pub fn set_bias(&mut self, vbe_bias: f64)

Set the DC bias operating point from circuit analysis. Called at compile time, not per-sample.

pub fn vbe_bias(&self) -> f64

Get the DC bias operating point.

pub fn set_vbe(&mut self, vbe: f64)

Set the base-emitter voltage (external control from input signal).

pub fn vbe(&self) -> f64

Get current Vbe.

pub fn set_v_max(&mut self, v_max: f64)

pub fn collector_current(&self, vce: f64) -> f64

Collector current Ic as a function of Vce, with Vbe held constant. This is the I-V characteristic seen at the WDF port.

pub fn collector_current_derivative(&self, vce: f64) -> f64

Derivative dIc/dVce for Newton-Raphson.

pub fn process(&mut self, a: f64, rp: f64) -> f64

WDF NR solve: incident wave → reflected wave.

Trait Implementations

impl Clone for BjtRoot

fn clone(&self) -> BjtRoot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for BjtRoot

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl NlDeviceIv for BjtRoot

fn iv(&self, v: f64) -> (f64, f64)

Return (current, d_current/d_voltage) at the given port voltage.

fn v_clamp(&self) -> (f64, f64)

Return (v_min, v_max) voltage clamping bounds for this device.