# BSIM3 MOSFETs

In this topic:

## Notes

The BSIM3 model is available with Pro and Elite versions of SIMetrix. Two versions are supplied namely 3.24 and 3.3.

BSIM3 models can be accessed using one of four values for the LEVEL parameter:

• LEVEL=7 specifies a PSpice compatible model
• LEVEL=8 specifies the standard Berkeley BSIM3 model.
• LEVEL=49 specifies the Hspice® implementation using the Hspice® junction capacitance model.
• LEVEL=53 is also a Hspice® version but uses the standard Berkeley junction cap model.

The following PSpice parameters are supported when using level 7: TT, L, W, RG, RD, RS, RB, RDS, JSSW

The following Hspice® parameters are supported when using level 49/53: CJGATE, HDIF, LDIF, WMLT, XL, XW, IS, N, NDS, VNDS, PHP, LMLT, CTA, CTP, PTA, PTP, TREF, RD, RS, RDC, RSC, CBD, CBS, FC, TT, LD, WD, EG, GAP1, GAP2, XLREF, XWREF, ACM, CALCACM, TLEV, TLEVC

The Hspice® noise model is also supported for NLEV=0,1 and 2.

The 'M' instance parameter has also been implemented with all variants. This specifies the number of equivalent parallel devices.

Additional temperature parameters: All variants support the TEMP and DTEMP instance parameters. TEMP specifies absolute temperature (Celsius) while DTEMP specifies the temperature relative to the circuit global temperature.

All variants support the model parameters T_MEASURED (equivalent to TNOM), T_ABS (as TEMP instance parameter) and T_REL_GLOBAL (as DTEMP instance parameter)

## Version Selector

The VERSION parameter can be specified to select which version is used. As detailed above, SIMetrix supports three different BSIM3 versions although 8 versions have been released by Berkeley. The following table shows which version will actually be used according to the VERSION parameter value.

 VERSION parameter Use BSIM3 Version 3.2 3.24 3.21 3.24 3.22 3.24 3.23 3.24 3.24 3.24 3.3 3.3 not specified 3.3
Note that a second decimal point will be ignored so 3.2.4 is the same as 3.24. If the version parameter is set to a value not listed above, SIMetrix will raise an error condition. This can be overridden by setting .OPTIONS AnyVersion.

## Model Parameters

The parameters describing BSIM3 are documented in the original Berkeley manual. See below. The following table lists parameters that are non-standard.

 Name Description Units Default TNOM, T_MEASURED Reference temperature; the temperature at which the model parameters were measured ° C 27 T_ABS If specified, defines the absolute model temperature overriding the global temperature defined using .TEMP ° C .TEMP T_REL_GLOBAL Offsets global temperature defined using .TEMP. Overridden by T_ABS ° C 0.0 VFBFLAG Capacitor model selector used by Hspice. An error will be raised if this parameter and the CAPMOD parameter are set to values not supported by SIMetrix 0 BINFLAG Parameter used by Hspice. An error will be raised if this parameter is set to a value other than zero 0 LREF Ignored WREF Ignored SFVTFLAG Ignored TT Level = 7 only. Reverse diode transit time S 0.0 L Level = 7 only. Channel length. Overridden by instance parameter m DEFL option W Level = 7 only. Channel width. Overridden by instance parameter m DEFW option RG Level = 7 only. Gate resistance Ω 0.0 RD Level = 7 only. Drain resistance Ω 0.0 RS Level = 7 only. Source resistance Ω 0.0 RB Level = 7 only. Bulk resistance Ω 0.0 RDS Level = 7 only. Drain-source leakage resistance Ω $\infty$ JSSW Level = 7 only. Alias for JSW. F/m 0.0

## Further Documentation

Original Berkeley documentation is provided on the CDROM and at our web site. Please visit Further Documentation for details.

## Process Binning

BSIM3 devices may be binned according to length and width. Refer to Model Binning for details.