Spice Syntax




Additional Information

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

Graphical representation


Cap1 13 0 1n 
CBYP 13 0 1UF 
COSC 17 23 10U 
CLOAD 2 10 10P 
CMOD 3 7 CMODEL L=10u W=1u
N+ and N- are the positive and negative element nodes, respectively.

VALUE is the capacitance in Farads. The (optional) initial condition is the initial (time-zero) value of capacitor voltage (in Volts). Note that the initial conditions (if any) apply 'only' if the UIC option is specified on the .TRAN control line. This is the more general form of the Capacitor presented in section 6.2, and allows for the calculation of the actual capacitance value from strictly geometric information and the specifications of the process.

If VALUE is specified, it defines the capacitance.

If MNAME is specified, then the capacitance is 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. Either VALUE or MNAME, LENGTH, and WIDTH may be specified, but not both sets.

The capacitor model contains process information that may be used to compute the capacitance from strictly geometric information.

name parameter units default example
CJ junction bottom capacitance - 5.e-5
CJSW junction sidewall capacitance F/meters - 2.e-11
DEFW default device width meters 1.e-6 2.e-6
NARROW narrowing due to side etching meters 0.0 1.e-7