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Cxxxx n1 n2 [model_name] value [IC=initial_condition] [TEMP=local_temp] |
[TC1=tc1] [TC2=tc2] [VC1=vc1] [VC2=vc2] [BRANCH=0|1] [M=mult] [DTEMP=dtemp] |
[ESR=esr] |
n1 | Node 1 |
n2 | Node 2 |
model_name | (Optional) Name of model. Must begin with a letter but can contain any character except whitespace and period '.' |
value | Capacitance (Farads) |
initial_condition | Initial voltage if UIC specified on .TRAN statement. |
local_temp | Capacitor temperature ($°$C) |
tc1 | First order temperature coefficient |
tc2 | Second order temperature coefficient |
vc1 | First order voltage coefficient |
vc2 | Second order voltage coefficient |
BRANCH | May be 0 or 1. 0 is the default. This parameter determines the internal formulation of the capacitor and affects how the IC parameter is implemented. When BRANCH=0, the capacitor looks like an open circuit during the DC operating point and the IC parameter has no effect unless UIC is specified for a transient analysis. If BRANCH=1, the capacitor looks like a voltage source during dc operating point with a magnitude equal to the value of the IC parameter. BRANCH=1 makes it possible to specify circuit startup conditions. See Alternative Initial Condition Implementations for an example. |
mult | Device multiplier. Equivalent to putting mult devices in parallel. |
dtemp | Differential temperature. Similar to local_temp but is specified relative to circuit temperature. If both TEMP and DTEMP are specified, TEMP takes precedence. |
esr |
Effective series resistance. If non-zero (the default value), a resistor of value esr will be connected in series with the capacitor. The resulting implementation of a series RC network is more efficient and offers better convergence than using a separate R and C. This is especially the case if the capacitor has a high value and is non-grounded.
Important: this resistor is noiseless; if the noise in the ESR is important in your design, you should use a separate resistor and omit this parameter in the capacitor. |
.model modelname CAP ( parameters ) |
Name | Description | Units | Default |
---|---|---|---|
C | Capacitor multiplier | 1 | |
TC1 | First order temperature coefficient | 1/$°$C | 0 |
TC2 | Second order temperature coefficient | 1/$°$C2 | 0 |
VC1 | First order voltage coefficient | Volt-1 | 0 |
VC2 | Second order voltage coefficient | Volt-2 | 0 |
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 | - |
T_REL_GLOBAL | Offsets global temperature defined using .TEMP. Overridden by T_ABS | C | 0.0 |
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