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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 coeff. |
Ohm/ºC |
0 |
- |
TC2 |
second order temperature coeff. |
Ohm/ºC/ºC |
0 |
- |
RSH |
sheet resistance |
Ohm/q |
- |
50 |
DEFW |
default width |
meters |
1e-6 |
2e-6 |
NARROW |
narrowing due to side etching |
meters |
0 |
1e-7 |
TNOM |
parameter measurement temperature |
ºC |
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: