Engee documentation

PNP Bipolar Transistor

NPN/PNP bipolar transistor using extended Ebers-Moll equations.

blockType: AcausalElectricPowerSystems.Semiconductors.BJT

npn bipolar transistor

NPN Bipolar Transistor

Path in the library:

/Physical Modeling/Electrical/Semiconductors & Converters/NPN Bipolar Transistor

pnp bipolar transistor

PNP Bipolar Transistor

Path in the library:

/Physical Modeling/Electrical/Semiconductors & Converters/PNP Bipolar Transistor

Description

Blocks PNP Bipolar Transistor and PNP Bipolar Transistor A variant of the Ebers-Moll equations is used to represent a bipolar transistor. The Ebers-Moll equations are based on two exponential diodes and two current-controlled current sources. The block uses the following improvements to this model:

  • The Earley effect.

  • Additional resistances of the base, collector and emitter.

  • Additional fixed capacities "base-emitter" and "base-collector".

The collector and base currents are:

For PNP transistor β ,

ββ .

For NPN transistor β ,

ββ ,

where

  • — base and collector currents (positive when flowing into the transistor);

  • — saturation current;

  • — base-emitter voltage and the collector base accordingly;

  • β — ideal maximum forward current gain ;

  • β — ideal maximum reverse current gain ;

  • — Earley’s direct voltage ;

  • — the elementary charge of an electron (1.602176e−19 Class);

  • — Boltzmann constant (1.3806503e−23 J/K).

  • — the temperature of the transistor, determined by the value of the parameter Measurement temperature.

You can set the behavior of the transistor using the parameters of the technical data sheet, which the unit converts into equations describing the transistor, or set the parameters of the equations directly.

For an NPN transistor, if or , then the corresponding exponential values in the equations are replaced by and . For a PNP transistor, if or , then the corresponding exponential values in the equations are replaced by and accordingly. This avoids the numerical problems associated with the gradient of the exponential function. with a steep slope at high values .

Similarly for an NPN transistor, if or , then the corresponding exponential values in the equations are replaced by and . For a PNP transistor, if or , then the corresponding exponential values in the equations are replaced by and

Additionally, you can set the fixed capacitances of the base-emitter and base-collector junctions. You can also set the connection resistance of the base, collector and emitter.

Simulation of capacity and charge

You simulate the capacity and charge using the parameters Base-collector junction capacitance and Base-emitter junction capacitance. You can also set the reverse recovery charge and its dynamics using the parameters Total forward transit time and Total reverse transit time. The equation that defines the base-collector charge:

,

where

  • — parameter value Total reverse transit time;

  • — collector-emitter current;

  • — parameter value Base-collector junction capacitance;

  • — base-collector voltage.

The equation that defines the base-collector charge and the capacitor current:

.

The equation that defines the base-emitter charge:

,

where

  • — parameter value Total forward transit time;

  • — collector current;

  • — parameter value Base-emitter junction capacitance;

  • — base-emitter voltage.

The equation that defines the base-emitter charge and the capacitor current:

.

Modeling of temperature dependence

By default, temperature dependence is not simulated, and the device is simulated at a temperature for which the block parameters are set. Additionally, you can enable simulation of the dependence of the transistor’s static behavior on temperature during simulation. The temperature dependence of the junction capacitances is not modeled, since this gives a much lower effect.

When the temperature dependence is taken into account, the defining equations of the transistor remain the same. Measurement temperature value , is replaced by the simulation temperature . Saturation current, , and the forward and reverse gain coefficients β and β they become a function of temperature according to the following equations:

,

ββ ,

ββ ,

where

  • — the temperature at which the transistor parameters are set, determined by the parameter value Measurement temperature;

  • — simulation temperature;

  • — saturation current at the measurement temperature;

  • — saturation current at the simulation temperature. It is this saturation current value that is used in the bipolar transistor equations when modeling the temperature dependence.

  • β and β — the gain coefficients of the forward and reverse stroke at the measurement temperature;

  • β and β — the gain coefficients of the forward and reverse stroke at the simulation temperature. It is these values that are used in the equations of bipolar transistors when modeling the temperature dependence.;

  • is the band gap for this type of semiconductor, measured in joules. For silicon, the value is usually assumed 1.11 eV (electronvolt), where 1 eV is equal to 1.602e−19 J;

  • — temperature exponent of saturation current;

  • — temperature coefficient of forward and reverse amplification;

  • — Boltzmann constant (1.3806503e−23 J/K).

Relevant values and they depend on the type of transistor and the semiconductor material used. In practice, the values are , and It must be adjusted to simulate the exact behavior of a particular transistor. Some manufacturers specify them in the SPICE Netlist (component connection list), where you can apply for these values. Otherwise, you can define the values , and using the data specified in the technical data sheet at a higher temperature . For this purpose, the block provides the possibility of parameterization according to the technical specification.

Ports

Conserving

# C — collector contact
electricity

Details

The electrical port connected to the collector contact of the transistor.

Program usage name

collector

# E — emitter contact
electricity

Details

The electrical port connected to the transistor emitter contact.

Program usage name

emitter

# B — base contact
electricity

Details

The electrical port connected to the base contact of the transistor.

Program usage name

base

Parameters

Main

# Transistor type — transistor type
NPN | PNP

Details

Choosing the type of transistor — NPN or PNP.

Values

NPN | PNP
Default value

—
Program usage name

type
Evaluatable

No

# Parameterization — parameterization of the block
Specify from a datasheet | Specify from equation parameters directly

Details

Select one of the following block parameterization methods:

  • Specify from a datasheet — provide the parameters that the unit converts into equations describing the transistor. The unit calculates the forward voltage of the Earley how , where — parameter value Collector current at which h-parameters are defined, and — parameter value Output admittance, h_oe. The block installs for a small signal value Forward current transfer ratio, h_fe. The unit calculates the saturation current by the specified value Voltage Vbe and Current Ib for voltage Vbe When equally 0. This method is used by default.

  • Specify from equation parameters directly — provide equation parameters , and .

Values

Specify from a datasheet | Specify from equation parameters directly
Default value

Specify from a datasheet
Program usage name

parameterization
Evaluatable

No

# Forward current transfer ratio, BF — direct current transmission coefficient

Details

The ideal maximum forward current gain.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Default value

100.0
Program usage name

beta_f
Evaluatable

Yes

# Saturation current, IS — saturation current
A | pA | nA | uA | mA | kA | MA

Details

Saturation current of the transistor.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Units

A | pA | nA | uA | mA | kA | MA
Default value

1e-14 A
Program usage name

I_sat
Evaluatable

Yes

# Forward Early voltage, VAF — Earley’s direct voltage
V | uV | mV | kV | MV

Details

In the standard Ebers-Moll equations, the gradient of the dependence curve from it is equal to zero in the normal hotspot. The additional forward Earley voltage increases this gradient. When extrapolating the linear domain, the intercept on the axis equal to − .

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Units

V | uV | mV | kV | MV
Default value

200.0 V
Program usage name

V_A
Evaluatable

Yes

# Forward current transfer ratio, h_fe — direct current transmission coefficient

Details

The current gain of a small signal.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Default value

100.0
Program usage name

h_fe
Evaluatable

Yes

# Output admittance, h_oe — complex conductivity
S | nS | uS | mS | 1/Ohm

Details

The derivative of the collector current with respect to the collector-emitter voltage for a fixed base current.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

S | nS | uS | mS | 1/Ohm
Default value

5e-05 1/Ohm
Program usage name

h_oe
Evaluatable

Yes

# Collector current at which h-parameters are defined — collector current at which h-parameters are determined
A | pA | nA | uA | mA | kA | MA

Details

The h-parameters depend on the operating point and are determined for a given collector current value.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

A | pA | nA | uA | mA | kA | MA
Default value

—
Program usage name

I_c_h
Evaluatable

Yes

# Collector-emitter voltage at which h-parameters are defined — collector-emitter voltage at which h-parameters are determined
V | uV | mV | kV | MV

Details

The h-parameters depend on the operating point and are determined for a given collector-emitter voltage value.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

V | uV | mV | kV | MV
Default value

—
Program usage name

V_ce_h
Evaluatable

Yes

# Voltage Vbe — base-emitter voltage
V | uV | mV | kV | MV

Details

Base-emitter voltage at base current . Data pair ] should be given for the case when the transistor is in the normal active region, i.e. not in the saturated region.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

V | uV | mV | kV | MV
Default value

—
Program usage name

V_be
Evaluatable

Yes

# Current Ib for voltage Vbe — current Ib for voltage Vbe
A | pA | nA | uA | mA | kA | MA

Details

The base current when the base-emitter voltage is . Data pair should be given for the case when the transistor is in the normal active region, i.e. not in the saturated region.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

A | pA | nA | uA | mA | kA | MA
Default value

—
Program usage name

I_be
Evaluatable

Yes

# Reverse current transfer ratio, BR — reverse current transmission coefficient

Details

The ideal maximum reverse current gain. This value is often not specified in manufacturers' technical data sheets, as it is not essential when the transistor is biased to operate in the normal active region. If the value is unknown and the transistor should not operate in the inverse region, use the default value of 1.

Default value

1.0
Program usage name

beta_r
Evaluatable

Yes

# Measurement temperature — Measurement temperature
K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR

Details

Temperature , at which the measured values are and , or .

Units

K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR
Default value

25.0 degC
Program usage name

T_measurement
Evaluatable

Yes

Ohmic Resistance

# Collector resistance, RC — collector resistance
Ohm | mOhm | kOhm | MOhm | GOhm

Details

The resistance on the collector.

Units

Ohm | mOhm | kOhm | MOhm | GOhm
Default value

0.01 Ohm
Program usage name

R_c
Evaluatable

Yes

# Emitter resistance, RE — emitter resistance
Ohm | mOhm | kOhm | MOhm | GOhm

Details

Resistance at the emitter.

Units

Ohm | mOhm | kOhm | MOhm | GOhm
Default value

1e-4 Ohm
Program usage name

R_e
Evaluatable

Yes

# Zero bias base resistance, RB — base resistance at zero offset
Ohm | mOhm | kOhm | MOhm | GOhm

Details

Resistance at the base at zero offset.

Units

Ohm | mOhm | kOhm | MOhm | GOhm
Default value

1.0 Ohm
Program usage name

R_b
Evaluatable

Yes

Capacitance

# Base-collector junction capacitance — base-collector junction capacity
F | pF | nF | uF | mF

Details

Parasitic capacitance at the base-collector junction.

Units

F | pF | nF | uF | mF
Default value

5.0 pF
Program usage name

C_bc
Evaluatable

Yes

# Base-emitter junction capacitance — base-emitter junction capacity
F | pF | nF | uF | mF

Details

Parasitic capacitance at the base-emitter junction.

Units

F | pF | nF | uF | mF
Default value

5.0 pF
Program usage name

C_be
Evaluatable

Yes

# Total forward transit time — total forward travel time
s | ns | us | ms | min | hr | d

Details

It represents the average transit time of non-primary carriers through the base region from the emitter to the collector and is often indicated by the TF parameter.

Units

s | ns | us | ms | min | hr | d
Default value

0.0 us
Program usage name

forward_transit_time
Evaluatable

Yes

# Total reverse transit time — total return trip time
s | ns | us | ms | min | hr | d

Details

It represents the average transit time of non-primary carriers through the base region from the collector to the emitter and is often indicated by the parameter .

Units

s | ns | us | ms | min | hr | d
Default value

0.0 us
Program usage name

reverse_transit_time
Evaluatable

Yes

Temperature Dependence

# Model Temperature Dependence — modeling of temperature dependence

Details

If the checkbox is unchecked (by default), then the temperature dependence is not modeled and the parameter values at the temperature are used. , set by the parameter Measurement temperature.

When checking this box, depending on the block parameterization method, you must also specify a set of additional parameters. If you are parameterizing a block from the technical data sheet, you must specify the values for the second pair of data. and at the second measurement temperature. If parameterization is performed by directly specifying equation parameters, it is necessary to specify values for , and .

Default value

false (switched off)
Program usage name

temperature_dependence
Evaluatable

No

# Forward current transfer ratio, h_fe, at second measurement temperature — direct current transmission coefficient, hfe, at the second measurement temperature

Details

The current gain of a small signal at the second measurement temperature. It must be specified at the same collector-emitter voltages and collector current as for the parameter Forward current transfer ratio, h_fe.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Default value

125.0
Program usage name

h_fe_T2
Evaluatable

Yes

# Voltage Vbe at second measurement temperature — voltage Vbe at the second measurement temperature
V | uV | mV | kV | MV

Details

Base-emitter voltage when the base current is , and the temperature is set to the second measurement temperature. Data pair It must be specified for the case when the transistor is in the normal active region, i.e. not in the saturation region.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

V | uV | mV | kV | MV
Default value

—
Program usage name

V_be_T2
Evaluatable

Yes

# Current Ib for voltage Vbe at second measurement temperature — current Ib for voltage Vbe at the second measurement temperature
A | pA | nA | uA | mA | kA | MA

Details

Base current when the base-emitter voltage is equal to , and the temperature is set to the second measurement temperature. Data pair It should be given for the case when the transistor is in the normal active region, that is, not in the saturation region.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

A | pA | nA | uA | mA | kA | MA
Default value

—
Program usage name

I_be_T2
Evaluatable

Yes

# Second measurement temperature — the temperature of the second measurement
K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR

Details

The second temperature , at which the measured values are и .

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from a datasheet.

Units

K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR
Default value

125.0 degC
Program usage name

T2
Evaluatable

Yes

# Current gain temperature coefficient, XTB — temperature current gain

Details

The value of the temperature current gain.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Default value

0.0
Program usage name

XTB
Evaluatable

Yes

# Energy gap, EG — the width of the forbidden zone
J | mJ | kJ | MJ | mW*hr | W*hr | kW*hr | MW*hr | eV | cal | kcal | Btu_IT

Details

The value of the width of the forbidden zone.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Units

J | mJ | kJ | MJ | mW*hr | W*hr | kW*hr | MW*hr | eV | cal | kcal | Btu_IT
Default value

1.11 eV
Program usage name

E_g
Evaluatable

Yes

# Saturation current temperature exponent, XTI — temperature exponent of saturation current

Details

The value of the temperature coefficient of the saturation current.

Dependencies

To use this parameter, set for the parameter Parameterization meaning Specify from equation parameters directly.

Default value

3.0
Program usage name

XTI
Evaluatable

Yes

# Device simulation temperature — Device simulation temperature
K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR

Details

Temperature , at which the device is modeled.

Units

K | degC | degF | degR | deltaK | deltadegC | deltadegF | deltadegR
Default value

25.0 degC
Program usage name

T_device
Evaluatable

Yes

Literature

  1. G. Massobrio and P. Antognetti. Semiconductor Device Modeling with SPICE . 2nd Edition, McGraw-Hill, 1993.

  2. H. Ahmed and P.J. Spreadbury. Analogue and digital electronics for engineers. 2nd Edition, Cambridge UniversityPress, 1984.