N-Channel MOSFET

Model of n-channel or p-channel MOSFET based on surface potential equations.

N-Channel MOSFET

n channel mosfet

P-Channel MOSFET

p channel mosfet

Description

The N-Channel MOSFET and P-Channel MOSFET blocks model an n-channel or p-channel field-effect transistor with a metal-oxide-semiconductor (MBD) structure based on surface potential equations.

The block also includes the ability to model thermal effects.

Model based on surface potential equations

The model based on surface potential equations takes into account the following effects:

A fully nonlinear capacitance model (including nonlinear Miller capacitance).
Charge conservation.
Carrier velocity saturation and channel length modulation.
Integrated diode.
Inverse recovery in the embedded diode model.
Influence of temperature on physical parameters.
Dynamic self-heating for the thermal effects modelling option (modelling the effect of self-heating on the electrical characteristics of the device).

This model is a simplified version of the standard PSP model [1], incorporating only some of it in order to find a balance between accuracy and complexity of the model. For more details on the physical assumptions of the phenomena included in this model, see [2].

The following are the surface potential equations for an n-channel MOSFET. The equations for a p-channel MOSFET are derived similarly, but the charges and currents are multiplied by -1.

The model is based on the Poisson equation:

where

- electrostatic potential;
- electron charge;
- concentration of acceptors in the substrate;
- dielectric constant of the semiconductor material (e.g. silicon);
- the difference between the intrinsic Fermi level and the Fermi level of bulk silicon;
- the quasipotential Fermi potential of the surface layer with respect to the bulk layer;
- temperature potential;
- Boltzmann constant;
- temperature.

The Poisson equation is used to derive the surface potential equation:

where

- is the applied gate-substrate voltage;
- is the stress of the flat zone;
- surface potential;
- substrate coefficient:
- specific surface capacitance.

The block uses an explicit approximation of the surface potential equation to avoid the need to numerically solve this implicit equation.

Once the surface potential is known, the drain current is determined as follows

where

- is the width of the device;
- channel length;
- mobility in weak fields;
- velocity saturation;
- surface potential difference between the drain and the source;
and - inversion charge densities at the source and the drain, respectively;
- average inversion charge density along the channel;
- mobility reduction factor. For more information, see the description of the Surface roughness scattering factor parameter;
- channel length modulation:

where
- - is the modulation coefficient of the channel length;
- - drain-substrate voltage;
- - drain-substrate voltage cut to the maximum value corresponding to velocity saturation or cut-off (whichever comes first);
- - channel length modulation voltage.

The unit calculates inversion charge densities directly from the surface potential.

The block also calculates nonlinear capacitances from the surface potential. The source and drain charge contributions are assigned using a bias-dependent Ward-Dutton charge separation scheme as described in [3]. These charges are calculated explicitly, so the charges are conserved in this model. Capacitive currents are calculated by taking the time derivatives of the corresponding charges. In practice, the charges within the modelling are normalised to the oxide capacitance and calculated in volts.

The gain of the MOSFET is determined as follows:

The threshold voltage for a shorted source-substrate junction is approximately determined as follows:

where is the surface potential at strong inversion.

In general, the three- and four-channel models consist of an intrinsic MOSFET defined by the surface potential formula, an integrated diode, series resistors, and fixed junction capacitances as shown in the schematic for an n-channel MOSFET.

n channel mosfet 1

n channel mosfet 2

Modelling an integrated diode

The block simulates an integrated diode with an exponential volt-ampere characteristic (VAC).

The junction capacitance and diffusion capacitance are calculated as:

where

- is the current through the diode;
- is the reverse saturation current;
- drain-substrate voltage;
- ideality factor;
- temperature potential;
- diode junction capacitance;
- junction capacitance at zero bias;
- voltage of the integrated diode;
- diffusion capacitance of the diode;
- transit time.

Modelling of temperature dependence

By default, temperature dependence is not considered and the device is modelled at the temperature for which the parameters are set. To take temperature dependence into account during simulation, set the Parameterization parameter to Model temperature dependence.

The surface potential equation model accounts for the effect of temperature on capacitive characteristics and also simulates the temperature dependence of the static behaviour of the transistor during the simulation.

Parameter Measurement temperature defines temperature , at which some parameters of the device are set. Parameters in the Temperature Dependence section set the modelling temperature and temperature dependence coefficients for other device parameters.

Thermal port

The unit has an optional thermal port hidden by default. To use the H thermal port, select the Enable thermal port checkbox.

Use the thermal port to simulate the effects of generated heat and unit temperature.

Ports

Conserving

# g — shutter
electricity

Details

The port associated with the gate.

Program usage name

gate

# d — effluent
electricity

Details

A port associated with a drain.

Program usage name

drain

# s — source
electricity

Details

Port associated with the source.

Program usage name

source

# H — heat port
heat

Details

Heat port.

Dependencies

To use this port, select the Enable thermal port checkbox.

Program usage name

thermal_port

# b — hull
electricity

Details

Port associated with an integrated diode on the substrate.

Dependencies

To use this port, set the Number of terminals parameter to Four.

Program usage name

body

Parameters

Main

# Transistor type — transistor type
N-Channel | P-Channel

Details

Transistor model type:

N-Channel - n-channel MOSFET;
P-Channel - p-channel MOSFET.

Values	`N-Channel` \| `P-Channel`
Default value	`—`
Program usage name	`type`
Evaluatable	No

# Number of terminals — contact parameterization
Three | Four

Details

Number of contacts in the block.

Values	`Three` \| `Four`
Default value	`Three`
Program usage name	`terminal_count`
Evaluatable	No

# Gain — amplification
A/V^2

Details

The gain of a MOSFET . This parameter primarily determines the linear region on the characteristic - .

Values	`A/V^2`
Default value	`18.0 A/V^2`
Program usage name	`reference_gain`
Evaluatable	Yes

# Flatband voltage — plane stress
V | MV | kV | mV

Details

The flat zone voltage defines the gate bias that must be applied to achieve a flat zone state on the silicon surface. It is possible to use this parameter to arbitrarily shift the threshold voltage due to differences in material yield performance and trapped charges at the interface or oxide. However, in practice, it is usually recommended to first change the threshold voltage using the Body factor and Surface potential at strong inversion parameters, and use this parameter only for fine tuning.

Values	`V` \| `MV` \| `kV` \| `mV`
Default value	`-1.1 V`
Program usage name	`V_flatband_reference`
Evaluatable	Yes

# Body factor — substrate coefficient
V^(1/2) | MV^(1/2) | kV^(1/2) | mV^(1/2)

Details

The substrate factor in the surface potential equation. This parameter primarily affects the threshold voltage.

Values	`V^(1/2)` \| `MV^(1/2)` \| `kV^(1/2)` \| `mV^(1/2)`
Default value	`3.5 V^(1/2)`
Program usage name	`body_factor`
Evaluatable	Yes

# Surface potential at strong inversion — surface potential at strong inversion
V | MV | kV | mV

Details

The value in the surface potential equation. This parameter also primarily affects the threshold voltage.

Values	`V` \| `MV` \| `kV` \| `mV`
Default value	`1.0 V`
Program usage name	`reference_potential_at_strong_inversion`
Evaluatable	Yes

# Velocity saturation factor — velocity saturation factor
1/V | 1/MV | 1/kV | 1/mV

Details

The value in the drain current equation. Use this parameter when a good linear fit results in too large a saturation current. Increasing the value of this parameter causes the saturation current to decrease. For high voltage devices, it is often the case that good linear mode matching results in too low a saturation current. In this case the gain and the drain ohmic resistance should be increased.

Values	`1/V` \| `1/MV` \| `1/kV` \| `1/mV`
Default value	`0.4 1/V`
Program usage name	`reference_velocity_saturation_factor`
Evaluatable	Yes

# Channel-length modulation factor — channel length modulation factor

Details

The coefficient , which is the multiplier of the logarithmic term in the equation for . This parameter describes the onset of channel length modulation. For device characteristics that exhibit positive conduction in saturation, increase the value of the parameter to match this behaviour. The value by default is 0, which means channel length modulation is off.

Default value	`0.0`
Program usage name	`modulation_factor`
Evaluatable	Yes

# Channel-length modulation voltage — channel length modulation voltage
V | MV | kV | mV

Details

The voltage in the equation for . This parameter controls the drain voltage at which channel length modulation begins to take effect.

Values	`V` \| `MV` \| `kV` \| `mV`
Default value	`5e-2 V`
Program usage name	`V_modulation`
Evaluatable	Yes

# Surface roughness scattering factor — surface roughness scattering coefficient
1/V | 1/MV | 1/kV | 1/mV

Details

Mobility reduction force. The mobility is equal to , where is the mobility in weak fields without the influence of surface scattering. The mobility reduction factor is defined as , where is the surface roughness scattering coefficient and is the voltage that corresponds to the effective vertical component of the electric field strength in the channel . For high vertical electric fields, electron mobility is approximately proportional to .

Values	`1/V` \| `1/MV` \| `1/kV` \| `1/mV`
Default value	`0.0 1/V`
Program usage name	`reference_surface_roughness_factor`
Evaluatable	Yes

# Linear-to-saturation transition coefficient — linear region-saturation transition coefficient

Details

This coefficient characterises the smoothness of the transition of the MOSFET characteristic from the linear region to saturation, especially if velocity saturation is enabled. Normally this parameter can be left at its By default value, but you can use it to fine-tune the characteristic curvature - . The expected range of values for this parameter is from 2 to 8.

Default value	`8.0`
Program usage name	`linear_to_saturation_transition_coefficient`
Evaluatable	Yes

Details

The temperature , at which the unit parameters are measured. If the value of Device simulation temperature is different from this value, the unit parameters will be determined according to the simulation temperature and reference temperature.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`25.0 degC`
Program usage name	`T_reference`
Evaluatable	Yes

Ohmic Resistance

# Source ohmic resistance — transistor source resistance
Ohm | GOhm | MOhm | kOhm | mOhm

Details

The source resistance of the transistor, that is, the series resistance associated with the source pin. The value must be greater than or equal to 0.

Values	`Ohm` \| `GOhm` \| `MOhm` \| `kOhm` \| `mOhm`
Default value	`2e-3 Ohm`
Program usage name	`R_s_reference`
Evaluatable	Yes

# Drain ohmic resistance — transistor drain resistance
Ohm | GOhm | MOhm | kOhm | mOhm

Details

The drain resistance of a transistor, that is, the series resistance associated with the drain pin. The value must be greater than or equal to 0.

Values	`Ohm` \| `GOhm` \| `MOhm` \| `kOhm` \| `mOhm`
Default value	`0.17 Ohm`
Program usage name	`R_d_reference`
Evaluatable	Yes

# Gate ohmic resistance — transistor gate resistance
Ohm | GOhm | MOhm | kOhm | mOhm

Details

The gate resistance of a transistor, that is, the series resistance associated with the gate contact. The value must be greater than or equal to 0.

Values	`Ohm` \| `GOhm` \| `MOhm` \| `kOhm` \| `mOhm`
Default value	`8.4 Ohm`
Program usage name	`R_g_reference`
Evaluatable	Yes

# Bulk ohmic resistance — transistor substrate resistance
Ohm | GOhm | MOhm | kOhm | mOhm

Details

Transistor substrate resistance, that is, the series resistance associated with the substrate contact.

Dependencies

To use this parameter, set the Number of terminals parameter to Four.

Values	`Ohm` \| `GOhm` \| `MOhm` \| `kOhm` \| `mOhm`
Default value	`2e-3 Ohm`
Program usage name	`R_b_reference`
Evaluatable	Yes

Channel Capacitances

# Oxide capacitance — oxide capacity
F | mF | nF | pF | uF

Details

The capacitance between the gate and the channel.

Values	`F` \| `mF` \| `nF` \| `pF` \| `uF`
Default value	`1500.0 pF`
Program usage name	`C_oxide`
Evaluatable	Yes

# Gate-source overlap capacitance — gate-to-source junction capacitance
F | mF | nF | pF | uF

Details

Fixed linear capacitance associated with the gate-source junction.

Values	`F` \| `mF` \| `nF` \| `pF` \| `uF`
Default value	`100.0 pF`
Program usage name	`C_gs_overlap`
Evaluatable	Yes

# Gate-drain overlap capacitance — gate-to-drain capacitance
F | mF | nF | pF | uF

Details

Fixed linear capacitance associated with the gate-to-drain junction.

Values	`F` \| `mF` \| `nF` \| `pF` \| `uF`
Default value	`14.0 pF`
Program usage name	`C_gd_overlap`
Evaluatable	Yes

Body Diode

# Reverse saturation current — reverse saturation current
A | MA | kA | mA | nA | pA | uA

Details

Current in the equations for the integrated diode.

Set this parameter to a non-zero value to simulate current flow through the integrated diode for applications where the MOSFET current changes sign during simulation, such as when the MOSFET drives an inductive load.

For applications where the MOSFET current never changes sign, such as in a small signal amplifier, set this parameter to 0 to increase the simulation speed.

Values	`A` \| `MA` \| `kA` \| `mA` \| `nA` \| `pA` \| `uA`
Default value	`5.2e-13 A`
Program usage name	`I_sat_reference`
Evaluatable	Yes

# Built-in voltage — integrated diode voltage
V | MV | kV | mV

Details

The embedded diode voltage in the equations for the embedded diode. This voltage only affects the junction capacitance equation. It does not affect the conduction current.

Values	`V` \| `MV` \| `kV` \| `mV`
Default value	`0.6 V`
Program usage name	`V_built_in`
Evaluatable	Yes

# Ideality factor — ideality factor

Details

The ideality factor in the equations for the integrated diode.

Default value	`1.0`
Program usage name	`ideality_factor`
Evaluatable	Yes

# Zero-bias junction capacitance — junction capacitance at zero bias
F | mF | nF | pF | uF

Details

The capacitance between drain and substrate at zero bias due to the integrated diode only, in the equations for the integrated diode.

Values	`F` \| `mF` \| `nF` \| `pF` \| `uF`
Default value	`480.0 pF`
Program usage name	`C_j0`
Evaluatable	Yes

# Transit time — transit time
d | s | hr | ms | ns | us | min

Details

Time in the equations for the integrated diode.

If the values of the Reverse saturation current and Transit time parameters are non-zero, the block includes reverse recovery in the embedded diode model.

Values	`d` \| `s` \| `hr` \| `ms` \| `ns` \| `us` \| `min`
Default value	`50e-9 s`
Program usage name	`transit_time`
Evaluatable	Yes

Temperature Dependence

# Parameterization — temperature dependence parameterization
None - Simulate at parameter measurement temperature | Model temperature dependence

Details

Select one of the following methods for parameterising the temperature dependence:

None - Simulate at parameter measurement temperature - the temperature dependence is not simulated. This is the By default method.
Model temperature dependence - Simulate temperature dependent effects. Specify the device modelling temperature value and temperature dependence coefficients for other block parameters.

Values	`None - Simulate at parameter measurement temperature` \| `Model temperature dependence`
Default value	`None - Simulate at parameter measurement temperature`
Program usage name	`enable_temperature_dependence`
Evaluatable	No

# Gain temperature exponent — degree of temperature dependence of the gain coefficient

Details

The gain of the MOSFET is assumed to be exponentially dependent on temperature: , where is the value of the Gain parameter and is the value of the Gain temperature exponent parameter.

Dependencies

To use this parameter, set the Parameterization parameter to `Model temperature dependence'.

Default value	`1.3`
Program usage name	`gain_temperature_exponent`
Evaluatable	Yes

# Flatband voltage temperature coefficient — coefficient in the temperature dependence of the plane zone stress
V/K

Details

The flatband voltage is assumed to be linearly dependent on temperature: , where is the value of the Flatband voltage parameter and is the value of the Flatband voltage temperature coefficient parameter.

Dependencies

To use this parameter, set the Parameterization parameter to `Model temperature dependence'.

Values	`V/K`
Default value	`5e-4 V/K`
Program usage name	`flatband_voltage_temperature_coefficient`
Evaluatable	Yes

# Surface potential at strong inversion temperature coefficient — coefficient in the temperature dependence of the surface potential at strong inversion
V/K

Details

The surface potential at strong inversion is assumed to depend linearly on temperature: , where is the value of Surface potential at strong inversion and is the value of Surface potential at strong inversion temperature coefficient.

Dependencies

To use this parameter, set the Parameterization parameter to `Model temperature dependence'.

Values	`V/K`
Default value	`-0.00085 V/K`
Program usage name	`potential_at_strong_inversion_temperature_coefficient`
Evaluatable	Yes

# Velocity saturation temperature exponent — degree of temperature dependence of velocity saturation

Details

The velocity saturation is assumed to be exponentially dependent on temperature: , where is the value of the Velocity saturation factor parameter and is the value of the Velocity saturation temperature exponent parameter.

Dependencies

To use this parameter, set the Parameterization parameter to `Model temperature dependence'.

Default value	`1.04`
Program usage name	`velocity_saturation_temperature_exponent`
Evaluatable	Yes

# Surface roughness scattering temperature exponent — degree index of temperature dependence of surface roughness scattering coefficient

Details

This parameter leads to a temperature-dependent decrease in the conductivity of the MOSFET at high gate voltage.

The surface roughness scattering factor is assumed to depend exponentially on temperature: , where is the value of the Surface roughness scattering factor and is the value of the Surface roughness scattering temperature exponent.

Dependencies

To use this parameter, set the Parameterization parameter to `Model temperature dependence'.

Default value	`0.65`
Program usage name	`surface_roughness_temperature_exponent`
Evaluatable	Yes

# Resistance temperature exponent — temperature dependence of resistance

Details

Series resistances are assumed to correspond to semiconductor resistances. Therefore, they decrease exponentially with increasing temperature: , where is , or for source, drain or gate resistance, respectively, is the value of the corresponding Source ohmic resistance, Drain ohmic resistance or Gate ohmic resistance parameter, and is the value of the Resistance temperature exponent parameter.

Dependencies

To use this parameter, set the Parameterization parameter to Model temperature dependence.

Default value	`0.95`
Program usage name	`resistance_temperature_exponent`
Evaluatable	Yes

# Body diode reverse saturation current temperature exponent — degree of temperature dependence of the reverse saturation current

Details

The inverse saturation current for an integrated diode is assumed to be proportional to the square of the concentration of intrinsic carriers: , where is the temperature-dependent effective density of states and is the temperature-dependent bandgap width for the semiconductor material. In order not to introduce another parameter for the temperature dependence, the temperature dependence of the forbidden zone width is neglected in the block and the forbidden zone width of silicon at 300 K (1.12 eV) is used for all types of devices. Thus, the temperature dependence of the reverse saturation current is defined as follows:

Where is the value of the Reverse saturation current parameter, is the Boltzmann constant, is the value of the Body diode reverse saturation current temperature exponent parameter. The value by default is 3 since for silicon is roughly proportional to . It is possible to account for the temperature dependence of the forbidden band width by adjusting the value of .

Dependencies

To use this parameter, set the Parameterization parameter to Model temperature dependence.

Default value	`3.0`
Program usage name	`reverse_saturation_current_temperature_exponent`
Evaluatable	Yes

Details

Temperature , for which the device simulation is performed.

Dependencies

To use this parameter, set the Parameterization parameter to Model temperature dependence.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`25.0 degC`
Program usage name	`T_device`
Evaluatable	Yes

Thermal Port

# Enable thermal port — switching on the heat port

Details

To enable thermal effects modelling, select the check box for this parameter.

Default value	`false (switched off)`
Program usage name	`has_thermal_port`
Evaluatable	No

# Thermal network — selection of an internal thermal model
Specify junction and case thermal parameters | Cauer model | Cauer model parameterized with Foster coefficients | External

Details

Select the internal thermal model:

Specify junction and case thermal parameters;
Cauer model;
`Cauer model parameterized with Foster coefficients';
External.

Values	`Specify junction and case thermal parameters` \| `Cauer model` \| `Cauer model parameterized with Foster coefficients` \| `External`
Default value	`Specify junction and case thermal parameters`
Program usage name	`thermal_network_parameterization`
Evaluatable	No

# Junction-case and case-ambient (or case-heatsink) thermal resistances, [R_JC R_CA] — thermal resistance vector
K/W

Details

The [R_JC R_CA] vector of two values of thermal resistance. The first value, R_JC, is the thermal resistance between the junction and the chassis. The second value, R_CA is the thermal resistance between the H port and the device enclosure.

Dependencies

To use this parameter, set the Thermal network parameter to Specify junction and case thermal parameters.

Values	`K/W`
Default value	`[0.0, 10.0] K/W`
Program usage name	`thermal_resistance_vector`
Evaluatable	Yes

# Thermal resistances, [R1 R2 ... Rn] — vector of thermal resistances for the Kauer model
K/W

Details

A vector of values of the thermal resistances represented by the Kauer elements in the thermal network. All these values must be greater than zero.

Dependencies

To use this parameter, set the Thermal network parameter to Cauer model.

Values	`K/W`
Default value	`[1.0, 3.0, 10.0] K/W`
Program usage name	`thermal_resistance_cauer_vector`
Evaluatable	Yes

# Thermal resistances, [R1 R2 ... Rn] — vector of thermal resistances for the Foster model
K/W

Details

A vector of values of thermal resistances represented by the Foster model coefficients in the heat network. All these values must be greater than zero.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model parameterised with Foster coefficients'.

Values	`K/W`
Default value	`[4.0, 6.0] K/W`
Program usage name	`thermal_resistance_foster_vector`
Evaluatable	Yes

# Thermal mass parameterization — heat capacity parameterization
By thermal time constants | By thermal mass

Details

Select the method for specifying the heat capacity:

By thermal time constants - parameterise the heat capacity in terms of thermal time constants. This value is used by default.
By thermal mass - parameterization of heat capacity values.

Dependencies

To use this parameter, set the Thermal network parameter to Specify junction and case thermal parameters, Cauer model or Cauer model parameterised with Foster coefficients.

Values	`By thermal time constants` \| `By thermal mass`
Default value	`By thermal time constants`
Program usage name	`thermal_mass_parameterization`
Evaluatable	No

# Junction and case thermal masses, [M_J M_C] — vector of heat capacity values for the Cowhert model
J/K | kJ/K

Details

The vector [M_J M_C] of two heat capacity values. The first value M_J is the heat capacity of the transition. The second value, M_C, is the heat capacity of the case.

Dependencies

To use this parameter, set the Thermal network parameter to `Specify junction and case thermal parameters' and the Thermal mass parameterization parameter to `By thermal mass'.

Values	`J/K` \| `kJ/K`
Default value	`[0.0, 1.0] J/K`
Program usage name	`thermal_mass_vector`
Evaluatable	Yes

# Thermal masses, [M1 M2 ... Mn] — vector of heat capacity values for the Kauer model
J/K | kJ/K

Details

A vector of heat capacity values, where is the number of Kauer model coefficients in the heat network. All these values must be greater than zero.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model' and the Thermal mass parameterization parameter to `By thermal mass'.

Values	`J/K` \| `kJ/K`
Default value	`[0.1, 0.3, 1.0] J/K`
Program usage name	`thermal_mass_cauer_vector`
Evaluatable	Yes

# Thermal masses, [M1 M2 ... Mn] — vector of heat capacity values for the Foster model
J/K | kJ/K

Details

A vector of heat capacity values, where is the number of Foster elements in the heat network. All these values must be greater than zero.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model parameterised with Foster coefficients' and the Thermal mass parameterization parameter to `By thermal mass'.

Values	`J/K` \| `kJ/K`
Default value	`[1.5, 3.0] J/K`
Program usage name	`thermal_mass_foster_vector`
Evaluatable	Yes

# Junction and case thermal time constants, [t_J t_C] — vector of thermal time constants
d | s | hr | ms | ns | us | min

Details

A vector [t_J t_C] of two values of thermal time constants. The first value, t_J, is the thermal time constant of the transition. The second value, t_C is the thermal time constant of the body.

Dependencies

To use this parameter, set the Thermal network parameter to Specify junction and case thermal parameters and the Thermal mass parameterization parameter to By thermal time constants.

Values	`d` \| `s` \| `hr` \| `ms` \| `ns` \| `us` \| `min`
Default value	`[0.0, 10.0] s`
Program usage name	`thermal_time_constant_vector`
Evaluatable	Yes

# Thermal time constants, [t1 t2 ... tn] — vector of thermal time constants for the Kauer model
d | s | hr | ms | ns | us | min

Details

A vector of values of thermal time constants, where is the number of Kauer elements in the thermal network. All these values must be greater than zero.

The heat capacity value is calculated as , where , and are the heat capacity, thermal time constant and thermal resistance for the -th Cauer element.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model' and the Thermal mass parameterization parameter to `By thermal time constants'.

Values	`d` \| `s` \| `hr` \| `ms` \| `ns` \| `us` \| `min`
Default value	`[1.0, 3.0, 10.0] s`
Program usage name	`thermal_time_constant_cauer_vector`
Evaluatable	Yes

# Thermal time constants, [t1 t2 ... tn] — vector of thermal time constants for the Foster model
d | s | hr | ms | ns | us | min

Details

A vector of values of thermal time constants, where is the number of Foster model coefficients in the thermal network. All these values must be greater than zero.

The heat capacity value is calculated as , where , and are the heat capacity, thermal time constant and thermal resistance for the -th Cauer element.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model parameterised with Foster coefficients' and the Thermal mass parameterization parameter to `By thermal time constants'.

Values	`d` \| `s` \| `hr` \| `ms` \| `ns` \| `us` \| `min`
Default value	`[6.0, 18.0] s`
Program usage name	`thermal_time_constant_foster_vector`
Evaluatable	Yes

Details

Vector [T_J T_C] of two temperature values. The first value, T_J, is the initial transition temperature. The second value, T_C is the initial case temperature.

Dependencies

To use this parameter, set the Thermal network parameter to Specify junction and case thermal parameters.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`[25.0, 25.0] degC`
Program usage name	`T_thermal_mass_vector_start`
Evaluatable	Yes

Details

A vector of temperature values. It corresponds to the temperature difference for each heat capacity in the model.

Dependencies

To use this parameter, set the Thermal network parameter to Cauer model.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`[25.0, 25.0, 25.0] degC`
Program usage name	`T_thermal_mass_cauer_vector_start`
Evaluatable	Yes

Details

A vector of absolute temperature values for each element of the Foster model.

Dependencies

To use this parameter, set the Thermal network parameter to `Cauer model parameterised with Foster coefficients'.

Values	`K` \| `degC` \| `degF` \| `degR` \| `deltaK` \| `deltadegC` \| `deltadegF` \| `deltadegR`
Default value	`[25.0, 25.0] degC`
Program usage name	`T_thermal_mass_foster_vector_start`
Evaluatable	Yes

Literature

[1] Gildenblat, G., et al. "Introduction to PSP MOSFET model." Proc. the MSM 2005 Int. Conf., Nanotech 2005. 2005.

[2] Van Langevelde, R., A. J. Scholten, and D. B. M. M. Klaassen. "Physical Background of MOS Model 11. Level 1101." Nat.Lab. Unclassified Report 2003/00239. April 2003.

[3] Oh, S-Y., D. E. Ward, and R. W. Dutton. "Transient analysis of MOS transistors." IEEE J. Solid State Circuits. SC-15, pp. 636-643, 1980.