Resistor

Spice Syntax

RXXXXXXX N1 N2 VALUE <VALUE> <MNAME> <L=LENGTH> <W=WIDTH> <TEMP=T>
RLOAD 2 10 10K RMOD 3 7 RMODEL L=10u W=1u

 

Additional Information

More details can be found in the HyperSpice chapter in Extended Definitions for Advanced Users.

Graphical Representation

Examples

R1 N1 N2 100 

RC1 12 17 1K

N1 and N2 are the two element nodes.

VALUE is the resistance (in ohms) and may be positive or negative but not zero. This is the more general form of the resistor and allows the modeling of temperature effects and also the calculation of the actual resistance value from strictly geometric information and the specifications of the process.

If VALUE is specified, it overrides the geometric information and defines the resistance.

If MNAME is specified, then the resistance may be calculated from the process information in the model MNAME and the given LENGTH and WIDTH.

If VALUE is not specified, then MNAME and LENGTH must be specified.

If WIDTH is not specified, then it is taken from the default width given in the model.

The (optional) TEMP value is the temperature at which this device is to operate, and overrides the temperature specification on the .OPTION control line. The resistor model consists of process-related device data that allow the resistance to be calculated from geometric information and to be corrected for temperature.

The parameters available are:
name parameter units default example
TC1 first order temperature coefficient. °C 0.0 -
TC2 second order temperature coefficient. 0.0 -
RSH sheet resistance Ω - 50
DEFW default width meters 1e-6 2.e-6
NARROW narrowing due to side etching meters 0.0 1.e-7
TNOM parameter measurement temperature °C 27 50

The sheet resistance is used with the narrowing parameter and L and W from the resistor device to determine the nominal resistance by the formula:

DEFW is used to supply a default value for W if one is not specified for the device. If either RSH or L is not specified, then the standard default resistance value of 1k is used.

TNOM is used to override the circuit-wide value given on the .OPTIONS control line where the parameters of this model have been measured at a different temperature. After the nominal resistance is calculated, it is adjusted for temperature by the formula: