Micro-Cap v7.1.6 / RM
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The Help system
The Help system provides information on the product in several ways:
•Contents (F1): This section provides help organized by topics.
•Search for Help On...: The search feature lets you access information by selecting a topic from an alphabetized list.
•Product Support: This option provides technical support contact numbers.
•Tip of the Day...: This option provides short tips on product features that are displayed each time MC7 is started.
•About Micro-Cap: This option shows the software version number.
•Statistics: This displays a list of statistics showing the key ID, MC7 version number and executable date. In an analysis it also shows the setup and run time, the number of analog and digital nodes, the number of data points calculated during the run, a list of the actual parts in the circuit after macro and subcircuit expansion, and a list of the number of iterations and solutions for the run.
•Key ID: This displays the security key ID which you sometimes need when upgrading the program or accessing technical support.
•Demos: These live demos show the sequence of actions involved in common functions. They include:
•General Demo: This provides a general overview of MC7. It includes each of the demos below and runs continuously until ESC is pressed.
•3D Plots Demo: This illustrates the use of 3D plots, which let you show how circuit waveforms or performance functions vary with two different parameters.
•Analog and Digital Demo: This shows how to mix analog and digital parts in a schematic and their analysis plots.
•Analysis Demo: This shows how to start and control an analysis.
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•Animation Demo: This illustrates the use of the animation feature, in which animated circuit components like LEDs and seven-segment displays respond to circuit states by turning on and off.
•Dynamic DC Demo: This demonstrates the Dynamic DC feature, which automatically calculates the DC operating point of the circuit as it is changed by the user.
•Filter Demo: This illustrates the use of the built-in active and passive filter design functions.
•Fourier Demo: This illustrates the use of the DSP functions to do Fourier analysis on circuit waveforms.
•Monte Carlo Analysis Demo: This illustrates the use of Monte Carlo analysis, which analyzes circuit behavior statistically as circuit parameters are varied around specified distributions.
•Optimizer Demo: This illustrates the use of the optimizer function to optimize and fine-tune circuits.
•Probe Demo: This illustrates the use of the Probe feature which lets you probe (point and click) the schematic for curves and waveforms.
•Performance Plots Demo: This illustrates the use of performance plots, which let you plot important circuit characteristics, like bandwidth or rise time versus model and other parameters.
•Schematic Demo: This shows how to create a schematic.
•Sensitivity Demo: This illustrates the Sensitivity analysis mode, which calculates the DC sensitivity of the circuit to one or more parameters.
•Stepping Demo: This illustrates the use of component parameter stepping, which lets you systematically step or change model and other parameters to see their effect on circuit behavior.
•Subcircuits Demo: This demo shows how to create and use
new subcircuits, including how to add them to the Component library.
• Transfer Function Demo: This illustrates the Transfer Function analysis mode, which calculates the DC transfer function.
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Chapter 3 The Shape Editor
What's in this chapter
This chapter describes the Shape editor. This editor is used to build new shapes or change existing shapes. Shapes are used to represent components in a schematic. Each shape is composed of objects such as lines, circles, and rectangles.
Upon exiting and saving changes, the shapes are available for use by the Component editor. That editor maintains the Component library, from which components are selected for use in schematics.
A large library of shapes is supplied with MC7, so most users will not need to use the Shape editor. For those who want to customize their shapes or add new ones, this chapter is for you.
Features new in Micro-Cap 7
•Drag copy command.
•Shape origin icon.
•Font size memory retained.
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The Shape editor layout
The Shape editor is selected from the Windows menu. Its display looks like this. There are five major regions:
Tool bar
Shape list box
Command buttons
Shape display
Figure 3-1 The Shape editor
Shape list box:
This list box displays all of the shapes currently in the library.
Command buttons:
Add: This command adds a new shape to the library.
Delete: This command deletes the currently selected shape.
Revert: This command restores the selected shape to its original version when the shape was first displayed. This only affects the displayed shape. Edits on other shapes during the current invocation of the Shape editor remain in effect. Selecting a new shape disables the Revert feature for the old shape. All edits on all shapes are temporary, however, and may be discarded when you exit the editor or close the file. Only when you exit or close the file are the changes saved to disk.
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Editor: This invokes the Object editor, which lets you edit the numeric parameters of the fundamental objects comprising the selected shape. This provides finer control over object size and shape than can be obtained with the normal mouse editing. Some features, such as the digital block pin symbols, are only changeable from the Object editor.
Close: This closes the Shape editor and, if any changes have been made, asks if you want to retain them.
Help: This accesses the Help system.
Tool bar:
The Tool bar provides the buttons to select tools for creating, editing, and viewing the selected shape. The tools and their properties are as follows:
New: (CTRL + N) This command creates a new shape library file. Any shapes added to it are available for use in the Component library.
Open: (CTRL + O) This command loads an existing shape library file. Its shapes are then available for use in the Component library.
Save As: This command saves the current shape library file under a new name specified by the user.
Remove: This command removes the currently loaded shape library file. Its shapes are no longer available for use in the Component library.
Undo: (CTRL + Z ) Most operations that change a shape can be reversed with the Undo command. Undo will only reverse the last change.
Cut: (CTRL + X) This command deletes the selected objects and copies them to the clipboard.
Copy: (CTRL + C) This command copies selected objects to the clipboard from where they may be pasted to the Shape display.
Paste: (CTRL + V) This command copies the contents of the clipboard starting at the last mouse position.
Clear: (DELETE) This command deletes the selected items without copying them to the clipboard.
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All: (CTRL + A) This command selects all items in the shape.
Select: Click this button to activate the Select mode. You must be in Select mode to edit or select a portion of shape for editing.
Pan: Click this button to activate the Pan mode. Panning is used to move the display view to see different parts of a large shape. As usual, you can also use the keyboard or the mouse. Mouse panning involves dragging the right mouse button and can be done in any mode. Alternatively, you can select this mode and drag with the left mouse button.
Rectangle: Click this button to create a rectangle in the shape by dragging the mouse in the Shape display. To change the shape of the rectangle, drag one of the eight handles (small black rectangles).
Diamond: Click this button to add a diamond in the shape by dragging the mouse. To change the shape of the diamond, drag one of the eight handles.
Ellipse: Click this button to add an ellipse to the shape by dragging the mouse in the Shape display. To change the shape of the ellipse, drag one of the eight handles. To create a circle, press the SHIFT key before dragging the mouse.
Arc: Click this button to add an arc to the shape by dragging the mouse in the Shape display. To change the shape of the arc, drag one of the eight handles.
Block: Click this button to create a digital block in the shape by dragging the mouse in the Shape display. To change the shape and number of leads, drag one of the eight handles. To edit the leads to reflect their function, select the block and then invoke the Object editor by clicking on its command button.
Line: Click this button to create a line in the shape by dragging the mouse in the Shape display. To change the direction or length of the line, drag on one of the two handles.
Closed Polygon: Click this button to add a closed polygon. Click the mouse in the Shape display, once for each vertex. There is no limit on the number of vertices. Double-click on the last vertex or click the right mouse button. This finishes the polygon by adding a final edge between the first and last vertices. To change the overall dimensions of the polygon, drag one of the handles.
Use the Object editor to edit the individual vertex coordinates.
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Open Polygon: Click this button to create an open polygon. Click the mouse in the Shape display, once for each vertex. There is no limit on the number of vertices. Double-click on the last vertex or click the right mouse button to end the polygon. To change the overall dimensions of the polygon, drag one of the eight handles. Use the Object editor to edit the individual vertex coordinates.
Included Shape: Click this button to include an existing shape in the current shape by clicking the mouse in the Shape display where you want the shape placed. This invokes a list of existing shapes. Choose the shape you want to include from this list. Once the shape is included, it can be dragged about.
Text: Click this button to add text to the shape by clicking the mouse in the Shape display where you want the text placed. This invokes a text dialog box. Type the text and press Enter. To edit text, double-click on it in Select mode.
Seven Segment LED: Click this button to create seven segment LED shapes for use in animated components.
LED diode: Click this button to create an LED diode shape for use in animated components.
Switch: Click this button to create a switch shape for use in animated components.
Current: Click this button to add a direction indicator for positive current. It is used only when the schematic Currents 
mode is enabled.
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Outline: Click this button to create outlined shapes, rather than filled shapes, when dragging a rectangle, diamond, ellipse, or closed polygon.
Fill: Click this button to create filled shapes, rather than outlined shapes, when dragging a rectangle, diamond, ellipse, or closed polygon.
Grid: Click this button to show the grid. The grid is a two-dimensional array of locations where shape objects must originate and terminate if their nodes are accessible in a schematic.
Grid Snap: Click this button to force the coordinates of all shape objects to occur at a grid point. This ensures that the coordinate points will be usable as connecting points (pins) in a schematic.
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Zoom-Out: Click this button to decrease the displayed image size. This does not affect the size of the image in the schematic.
Zoom-In: Click this button to increase the displayed image size. This does not affect the size of the image in the schematic.
To Front: Click this button to send the selected object in an overlapping stack of objects to the front.
To Back: Click this button to send the selected object in an overlapping stack of objects to the back.
Next Object: Click this button to select a different object in a stack of overlapping objects. Click the button until the one you want is selected.
Font: Click this button to change the text attributes of any selected text. This also changes the default text attributes that will be used the next time text is added to the shape.
Flip X: This command rotates the selected region about the X axis in 180 degree increments, essentially flipping the object or group about the X axis.
Flip Y: This command rotates the selected region about the Y axis in 180 degree increments, essentially flipping the object or group about the Y axis.
Rotate: This command rotates the selected region about the Z axis (the Z axis is perpendicular to the schematic plane) in 90 degree increments, producing four distinct orientations.
Mirror: This command creates a mirror image copy of the selected region. It invokes the Mirror dialog box which lets you choose a vertical or horizontal reflection and whether you want to copy the text in the region. A vertical reflection produces a copy vertically below the original region. A horizontal reflection produces a copy horizontally to the right of the original region.
Shape drawing window:
This window shows the selected shape. You can change the image size, and pan or scroll the window to see larger shapes.
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The Object editor
Most objects can be created and edited by simple mouse operations. For the closed and open polygons and the block, it is necessary to use the Object editor to edit the object's characteristics. For other objects, it is sometimes convenient to use the editor to tweak the numeric values that control the size and shape of the object, after the object has been roughly drawn with the mouse.
The Object editor is invoked by clicking the Editor button or by double-clicking on the object that you want to edit. The editor looks like this:
Pin selector
Tool bar
Object list box
Object parameters
Figure 3-2 The Object editor
There are five major parts to the Object editor:
Tool bar:
This lets you select new objects to add to the existing list. Click on an object to add it to the object list.
Object list box:
This shows the objects that the shape is composed of.
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Pin selector:
When the selected object is a block, this shows the pin symbols. These symbols are intended to iconically convey the existence and function of the pin. They do not, of course, affect the actual behavior of the pins that they represent. There are five basic pin symbols:
Open: No pin at this location.
Clock: A clock pin.
Inversion: A logical inversion.
Inverted Clock: An inverted clock pin.
Normal: No indication of the pin function.
Object parameters:
These fields hold the numeric values that characterize the object. Rectangles, diamonds, ellipses, arcs, lines, and text use two sets of coordinates to define the coordinates of two opposite corners of the objects's bounding box. The bounding box is the rectangle that contains the object. Polygon parameters are a set of N coordinates of the form X,Y. The Included Shape parameters are the coordinates of the position where the included shape is placed. Coordinates are numerically equal to the number of grids from the upper left origin at the highest scale.
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