Micro-Cap v7.1.6 / RM

Panning the plot

Panning means to change the plot view without changing the scale. It is usually employed after zooming in. There are two ways to pan the plot:

Keyboard:

Use CTRL + LEFT ARROW to pan the plot to the left. Use CTRL + RIGHT ARROW to pan the plot to the right. Use CTRL + UP ARROW to pan the plot up.

Use CTRL + DOWN ARROW to pan the plot down.

Keyboard panning is available from any mode.

Mouse:

Cursor mode: Press and hold the CTRL key down. Place the mouse in the plot window and drag the right mouse button in the desired direction.

Other modes: Place the mouse in the plot window and drag the right mouse button in the desired direction.

Panning moves only the curves in the selected plot group. Click in another plot group, click on a plot expression in another plot group, or use the Tab key to select a different plot group.

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Tagging the plot

Tagging is a way of both measuring and documenting a data point or difference between two data points. Tagging can be done on a single curve, between two points on a single curve, or between two points on two curves. There are three tagging modes:

Point Tag mode: This mode lets you tag a data point on a curve. It shows the X expression and Y expression values at the data point. This mode is very useful for measuring or documenting the exact time of a digital event, or the peak or valley of an analog curve.

Vertical Tag mode: This mode lets you drag a tag between two data points on one or two curves. It shows the vertical difference between the Y values at the two data points.

Horizontal Tag mode: This mode lets you drag a tag between two data points on a single curve or two different curves. It shows the horizontal difference between the X expression values at two data points. It is most useful for measuring the time difference between two digital events such as the width of a pulse or the time delay between two events.

There are also several immediate commands for tagging the data points at the numeric cursors.

•Tag Left Cursor: (CTRL + L) This command attaches a tag to the left cursor data point on the selected curve.

•Tag Right Cursor: (CTRL + R) This command attaches a tag to the right cursor data point on the selected curve.

•Tag Horizontal: (SHIFT + CTRL + H) This command attaches a horizontal tag from the left to the right cursor, showing the difference between the two X expression values.

•Tag Vertical: (SHIFT + CTRL + V) This command attaches a vertical tag from the left to the right cursor, showing the difference between the two Y expression values.

The numeric format of the tag numbers is determined by the numeric format set at Options / Preferences / Format / Analysis Plot Tags.

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Adding graphics to the plot

You can add graphic symbols to the analysis plot when in the Graphics mode. To invoke the Graphics mode, click on the graphics button, and select one of the objects from the menu that pops up. To add one of the graphic objects, click and drag in the plot area. The objects are:

Rectangle

Line

Ellipse

Diamond

Arc

Pie

Polygon

Each of these objects can be edited after creation by double-clicking on them. This invokes a dialog box that lets you change their border and fill characteristics.

The polygon object allows direct numerical editing of the polygon vertices. It is intended as a design template, a region describing the area that a curve or curve may occupy and still be within specification. The filter designer adds a polygon to the AC plot to indicate the acceptable region for the Bode plot from the user's filter specs. You can use the constants MIN and MAX to specify the plot minimum and maximum coordinates easily.

To see an example of a design polygon, create a filter circuit using the active or passive filter functions from the Design menu and run an AC analysis. Enter Select mode and then double-click on the yellow polygon to see its properties, including its border, fill, and vertex structure.

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Scope menu

The Scope menu provides these options:

•Delete All Objects: This command removes all objects (shapes, tags, or text) from the analysis plot. To delete an object, select it by clicking on it, then press CTRL + X or the DELETE key. To delete all objects use CTRL + A to select all objects, then press CTRL + X or the DELETE key.

•Auto Scale: This command scales the plot group containing the selected curve. F6 may also be used. The selected curve is the one whose Y expression isunderlined.

•Restore Limit Scales: This command restores the range scales to the values in the Analysis Limits dialog box. CTRL + HOME may also be used.

•View: The view options only affect the display of simulation results, so

you may change these after a run and the screen is redrawn accordingly. These options may also be accessed through Tool bar icons shown below.

•Data Points: This marks the actual points calculated by the program on the curve plot. All other values are linearly interpolated.

•Tokens: This adds tokens to each curve plot. Tokens are small graphic symbols that help identify the curves.

•Ruler: This substitutes ruler tick marks for the normal full screen X and Y axis grid lines.

•Plus Mark: This replaces continuous grids with "+" marks at the intersection of the X and Y grids.

• Horizontal Axis Grids: This adds grids to the horizontal axis.

•Vertical Axis Grids: This adds grids to the vertical axis.

•Minor Log Grids: This adds minor log grid lines between the major grids to any axis which uses the log option.

• Baseline: This adds a plot of the value 0.0 for use as a reference.

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•Go to X: (SHIFT + CTRL + X) This command lets you move the left or right cursor to the next instance of a specific value of the X expression of the selected curve. It then reports the Y expression value at that data point.

•Go to Y: (SHIFT + CTRL + Y) This command lets you move the left or right cursor to the next instance of a specific value of the Y expression of the selected curve. It then reports the X expression value at that data point.

•Go to Performance: This command calculates performance function values on the Y expression of the selected curve. It also moves the cursors to the measurement points. For example, you can measure pulse widths and bandwidths, rise and fall times, delays, periods, and maxima and minima.

•Go to Branch: This command lets you select which branch of a curve to place the left and right cursors on. The left cursor branch is colored in the primary select color and the right cursor branch in the secondary select color.

•Tag Left Cursor: (CTRL + L) This command attaches a tag to the left cursor data point on the selected curve.

•Tag Right Cursor: (CTRL + R) This command attaches a tag to the right cursor data point on the selected curve.

•Tag Horizontal: (SHIFT + CTRL + H) This command places a horizontal tag between the left and the right cursor, showing the difference between the two X expression values.

•Tag Vertical: (SHIFT + CTRL + V) This command places a vertical tag between the left and the right cursor, showing the difference between the two Y expression values.

•Align Cursors: This option, available only in Cursor mode, forces the numeric cursors of different plot groups to stay on the same data point.

•Keep Cursors on Same Branch: When stepping produces multiple runs, one line is produced for each run for each plotted expression. These lines are called branches of the curve or expression. This option forces the left and right cursors to stay on the same branch of the selected curve when the UP ARROW and DOWN ARROW cursor keys are used to move the numeric cursors among the several branches. If this option is disabled the cursor keys will move only the left or right numeric cursors, not both, allowing them to occupy positions on different branches of the curve.

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•Same Y Scales: This option forces all curves in a plot group to use the same Y scale. If the curves have different Y Range values, one or more Y scales will be drawn, which may lead to crowding of the plot with scales.

•Thumb Nail Plot: This option draws a small guide plot which gives a global view of where the current plot(s) are on the whole curve. You can also select different views by dragging a box over the curve. Dragging the cursors on the guide plot drags them on the main plot.

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The Plot Properties dialog box

Curve display and format can be changed after the run with the Properties dialog box. It looks like this:

Figure 13-1 The Plot Properties dialog box

The Plot Properties dialog box lets you control the analysis plot window. It can be used for controlling curve display after or even before the plot. Before a plot exists, you can access the dialog box by clicking on the Properties button in the Analysis Limits dialog box. The dialog box provides the following choices:

• Plot

Curves: This lets you select the curve that Plot and Graph fields apply to.

Title: This lets you specify what the plot title is to be. If the Auto button is checked, the title is automatically created from the circuit name and analysis run details.

Curve: This check box controls the plotting of the selected curve. To hide the curve, remove the check mark by clicking in the box.

Plot Group: This controls the plot group number.

Plot Type: This controls the plot type, rectangular, polar, or Smith chart. The latter two are available only on AC analysis.

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