# Piecewise Linear Current Source

Time-dependent current source using lookup table

**Libraries:**

Simscape /
Electrical /
Sources

Simscape /
Electrical /
Additional Components /
SPICE Sources

## Description

The Piecewise Linear Current Source block represents a current source that you specify in lookup table form using a vector of time values and a vector of the corresponding current values. You must specify at least two time-current value pairs. The block generates a time-dependent current based on these time-current values using the selected interpolation and extrapolation methods. You have a choice of two interpolation methods and extrapolation methods. The output current is independent of the voltage across the terminals of the source.

The block uses a small conductance internally to prevent numerical simulation issues. The
conductance connects the **+** and **-** ports of the device
and has a conductance *GMIN*:

By default,

*GMIN*matches the**GMIN**parameter of the Environment Parameters block, whose default value is`1e–12`

`1/Ohm`

.To change

*GMIN*, add an Environment Parameters block to your model and set the**GMIN**parameter to the desired value.

## Examples

## Ports

### Conserving

## Parameters

## References

[1] D. Kahaner, Cleve Moler, and Stephen Nash *Numerical
Methods and Software*. Prentice Hall, 1988.

[2] W.H. Press, B.P. Flannery, S.A. Teulkolsky, and W.T. Wetterling.
*Numerical Recipes in C: The Art of Scientific Computing*. Cambridge
University Press, 1992.

## Extended Capabilities

## Version History

**Introduced in R2008a**