Struct MosfetModel 

pub struct MosfetModel {
    pub vth: f64,
    pub kp: f64,
    pub lambda: f64,
    pub is_n_channel: bool,
}

Enhancement-mode MOSFET model parameters.

Uses the SPICE Level 1 square-law model for drain current:

• Cutoff: Ids = 0 when |Vgs| < |Vth|
• Triode: Ids = Kp * [(Vgs-Vth)*Vds - 0.5*Vds^2]
• Saturation: Ids = 0.5*Kp * (Vgs-Vth)^2 * (1 + lambda*|Vds|)

Fields

vth: f64

Threshold voltage (V). N-channel: positive, P-channel: negative.

kp: f64

SPICE Level 1 transconductance parameter (A/V²), before the 1/2 square-law saturation factor.

lambda: f64

Channel-length modulation parameter (1/V). Typical: 0.01-0.1.

is_n_channel: bool

True for N-channel, false for P-channel.

Implementations

impl MosfetModel

pub fn n_2n7000() -> MosfetModel

2N7000 N-channel enhancement MOSFET.

Very common in guitar pedal clipping (Fulltone OCD, modern drives). Low threshold voltage, small package, fast switching.

pub fn n_irf520() -> MosfetModel

IRF520 N-channel power MOSFET.

Higher current capability, used in some high-headroom drive circuits.

pub fn p_bs250() -> MosfetModel

BS250 P-channel enhancement MOSFET.

Used in some boost circuits and complementary configurations.

pub fn p_irf9520() -> MosfetModel

IRF9520 P-channel power MOSFET.

pub fn ids(&self, vgs: f64, vds: f64) -> f64

Drain current Ids(Vgs, Vds) — enhancement-mode square-law model.

• Cutoff: Ids = 0 when the channel is off (N: Vgs <= Vth, P: Vgs >= Vth)
• Triode: Ids = Kp * [Vov*|Vds| - 0.5*Vds²] * sign(Vds)
• Saturation: Ids = 0.5*Kp * Vov² * (1 + lambda*|Vds|) * sign(Vds)

The channel conducts symmetrically in both Vds polarities (drain and source are interchangeable in the square-law model).

pub fn ids_vds_derivative(&self, vgs: f64, vds: f64) -> f64

Derivative dIds/dVds at fixed Vgs.

Returns LEAKAGE_CONDUCTANCE in cutoff so Newton-Raphson always sees a non-zero slope.

Trait Implementations

impl Clone for MosfetModel

fn clone(&self) -> MosfetModel

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MosfetModel

impl Debug for MosfetModel

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

Formats the value using the given formatter.