functionMOSeq1

Computation of injected drain-source current for Levels = 0,1

Information

This function implements a Spice-style Level-1 model of the current flowing between drain and source of a MOSFET in accrodance with the theory of Shichman and Hodges [1]. It is a simple model that computes the current in its linear and saturation regions only. No channel modulation effects are considered, and the current is set equal to zero in the subthreshold region of the device.

The current injection model is identical for Modelica-Spice Level-0 and Level-1.

The model comments the equations by providing the corresponding equation numbers from [2].


Input variables:

 vds:     Drain-source voltage (Volt)

 vgs:     Gate-source voltage (Volt)

 vbs:     Bulk-source voltage (Volt)

 Tdev:    Device temperature (K)

 sig:     Indicator of operating mode
            sig = +1:  direct mode
            sig = -1:  reverse mode (source and drain are flipped)


Input parameters:

 Type:    Type of MOSFET (default value = 1)
            Type = +1:  NMOS
            Type = -1:  PMOS

 Tnom:    Reference temperature (default value = 300.15 K)

 VFB:     Flat band voltage at reference temperature (default value = 0 Volt)

 KP:      Transconductance parameter at reference temperature (default value = 0 Amp/Volt2)

 GAMMA:   Body-effect parameter (default value = 0 Volt0.5)

 PHI:     Surface inversion potential at reference temperature (default value = 0 Volt)

 LAMBDA:  Channel length modulation  (default value = 0 1/Volt)

 L:       Channel length (default value = 1e-4 m)

 W:       Channel width (default value = 1e-4 m)

 EG:      Energy gap for temperature effect on saturation current at 0 K (default value = 1.11 Volt)


Output variables:

 isd0:    Drain-source current (Amp)

 Vfb:     Flat band voltage at device temperature (Volt)

 Vth:     Threshold voltage (Volt)

 vdsat:   Saturation voltage (Volt)


References:

  1. Shichman, H. and D.A. Hodges (1968), "Modeling and Simulation of Insulated-Gate Field-Effector Transistor Switching Circuits," IEEE J. Solid-State Circuits, 3(3), pp. 285-289.
  2. Massobrio, G. and P. Antognetti (1993), Semiconductor Device Modeling with Spice, 2nd edition, McGraw Hill, New York.

Inputs

TypeNameDefaultDescription
Modelica.SIunits.VoltagevdsDrain-source voltage
Modelica.SIunits.VoltagevgsGate-source voltage
Modelica.SIunits.VoltagevbsBulk-source voltage
Modelica.SIunits.TemperatureTdevDevice temperature
Realsigsign(vds)
IntegerTypeType=1 for NMOS; Type=-1 for PMOS
Modelica.SIunits.TemperatureTnomReference temperature
Modelica.SIunits.VoltageVFBFlat band voltage at reference temperature
Modelica.SIunits.TransconductanceKPTransconductance parameter at reference temperature
RealGAMMABody-effect parameter
Modelica.SIunits.VoltagePHISurface inversion potential at reference temperature
Modelica.SIunits.InversePotentialLAMBDAChannel length modulation
Modelica.SIunits.LengthLEffective hannel length
Modelica.SIunits.LengthWEffective channel width
Modelica.SIunits.VoltageEGEnergy gap for temperature effect on saturation current at 0 K

Outputs

TypeNameDefaultDescription
Modelica.SIunits.Currentids0Injected drain-source current
Modelica.SIunits.VoltageVfbFlat band voltage at device temperature
Modelica.SIunits.VoltageVthThreshold voltage
Modelica.SIunits.VoltagevdsatSaturation voltage