cap_sw :
A switchable capacitor circuit element.
The cap_sw
primitive represents a two-terminal capacitor of which capacitance can be controlled by a third input C
. In other words, the capacitance between the two terminals pos
and neg
switches to a new value indicated by the real-typed input C
whenever its value changes. The total charge stored on the capacitor is preserved before and after each switching event.
Since every value-change event of the input C
triggers a new computation, the cap_sw
primitive is not recommended for modeling capacitance that continuously varies with a voltage or current (use a cap_var
primitive for nonlinear, voltage-dependent capacitance). The cap_sw
primitive is intended mainly for capacitance that switches between discrete levels (e.g. capacitance programmable via digital control).
Note that this primitive is a pseudo-module to describe a structural netlist of electrical circuits and not a behavioral model by itself. The XMODEL simulator extracts an event-driven behavioral model at run-time based on the circuit network described by these circuit-level pseudo-modules.
Input/Output Terminals
Name | I/O | Type | Description |
pos | input | xreal | positive terminal |
neg | input | xreal | negative terminal |
C | input | real | capacitance |
Parameters
Name | Type | Default | Unit | Description |
ic | real | `NaN | volts | initial condition |
Cpos | real | 0.0 | farads | pos-to-gnd capacitance |
Cneg | real | 0.0 | farads | neg-to-gnd capacitance |