Interactive Cell Size Calculator

The interactive Cell Size Calculator allows you to enter critical dimensions of your circuit to calculate an optimal cell size which provides the desired analysis accuracy while using the minimum of processing resources. The contents of the dialog box is updated as you change your input values. When you are satisfied with the cell size, you may close the cell calculator. When the cell calculator is closed, the cell size is updated in the  Box page of the Circuit Settings dialog box.

Note: Entries in this dialog box are only saved as long as the circuit is open in the project editor. The settings are not saved in the project file.

Direction: Select the X radio button to calculate the x dimension of the cell and select the Y radio button to calculate the y dimension of the cell. The rest of the calculator refers to whichever direction is selected here. If X is selected, the Cell Width(X) text entry box is enabled. If Y is selected, the Cell Width(Y) is enabled.

Tolerance: To enter the tolerances as a percentage, click on the % radio button. To enter the tolerances as an absolute value, click on the length unit (i.e. mils, inches, etc.) button. Whichever length unit is in use for this project appears here.

Set Tolerances To: Click on this button to update all the tolerances in the presently selected direction to the default value input in the text entry box just below the button. When you input a new tolerance, the results fields, including the calculated cell dimension, actual values and tolerances are cleared. You need to click on the Calculate button to update these fields.

Target: Enter each critical dimension for the direction selected in a text entry box in the Target column. You are required to enter at least two targets. These targets and their respective tolerances will be used to calculate the cell size.

Tolerance: Enter the tolerance for each target in these text entry boxes. The tolerance may be entered as an absolute value or as a percentage. The type of tolerance is selected using the Tolerance radio buttons above. You may enter a separate tolerance for each target. If you enter a tolerance and click on the Set Tolerances To button, all the tolerances for each target are set to that value.

Calculate: Click on this button once you have entered all the critical dimensions in the Target entries and set your tolerances for each target. The optimal cell size for the direction selected (x or y) is output in the appropriate Cell Width text entry box. The actual size and the error is displayed for each target in the columns to the right.

Cell Width (X) and Cell Height (Y): The calculated value, which is entered in the box settings dialog box when the calculator is closed, appears here when you click on the Calculate button. If you wish to modify the calculated value, you may enter another value here. If you edit this value and enter a new one, you should click on the Update button to update the Actual and Error values in the two right-hand columns above. If the value you input causes the error to go outside the specified tolerance, than these values appear in red.

Update: Click on this button if you have edited the Cell Width value. The update recalculates the actual value and error for each target. If the resulting error is greater than the specified tolerance, then the results are displayed in red.

Estimate Memory: Click on this button to get an estimate of the amount of memory needed to analyze the circuit using the present cell size in the cell width entry box.