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DO YOU EXCEL IN ELECTRONICS?

Part 2: The Benefits of Using Excel
by Aubrey Kagan

Start ý Standard Values ý Saving Macros ý Simple Amplifier ý LM317 Calculation ý Goal Seek ý Use of Functions ý Additional Options ý Source and PDF

ADDITIONAL OPTIONS

Youýre already creating a generic model for the LM317, why not add some more to it? I suggest a maximum/minimum analysis based on the maximum and minimum values of the component parameters (see Photo 6 and LM317.xls (download Excel files)).

The results show the minimum and maximum values of the programmed output voltage based on 1% resistors and the extremes of LM317 parameters as found in the datasheet. In addition, itýs also simple to calculate the maximum allowable input voltage. The result cells have been formatted for two decimal places. Opening the file and clicking on the cells will show the formulas used.

Note that the macro has been edited to activate the LM317.xls workbook instead of the Example3f.xls workbook. This is necessary, otherwise an error will result from an non-found workbook.

Anytime you wish to design in LM317, simply open the workbook. Youýll be prompted for the desired voltage, and in a flash, youýll be provided with the optimal resistor values and a maximum/minimum voltage analysis.

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