Semiconductor Resistor Model

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Semiconductor Resistor Model

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: