Introduction

Lcapy-tk allows a circuit schematic to be quickly created. By selecting a component, the potential difference across the component or the current through the component can be displayed symbolically.

The schematic can be exported in a fancier form, as a PNG, PDF, SVG or image. Alternatively, the schematic can be converted to Circuitikz macros.

Editing

Click on the grid to place a red positive node then click elsewhere to place a blue negative node. Then enter c for a capacitor, i for a current source, l for an inductor, r for a resistor, v for a voltage source, etc. Alternatively, use the Components menu. The escape key will remove both the positive and negative nodes.

The attributes of a component (name, value, etc.) can be edited by right clicking on a component. Note, voltage and current sources default to DC. Select kind as step for transient analysis or specify the value as a time domain function.

The attributes of a node can be edited by right clicking on a node. This is useful for defining a ground node.

Analysis

Select a component and use Inspect (ctrl+i) to find the voltage across a component or the current through a component. Note the polarity is defined by the red (plus) and blue (minus) highlighted nodes.

Note, voltage and current sources default to DC. This can be changed by right clicking on the source and selecting DC, AC, step, or arbitrary. With arbitrary, the value can be an arbitrary time-domain expression, for example, 4 * H(t) + 2, where H(t) is the Heaviside step.

Preferences

The preferences dialog controls the drawing style.

Additional documentation

For further information about Lcapy, see https://lcapy.readthedocs.io