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Calculators and Solvers

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Supported number formats

    You can enter values into the solvers in one of five different formats.  They are:


                     Format                      Description

                       xxx.xx       Using a “.” to indicate the decimal part of the number

                                      x,xxx.x      Using an optional “,” as a thousands separator

                                      x xxx.x      Using an optional space as a thousands separator

                                      xx.xxM      Using Engineering Notation (see below) with a “.”

                                      xxMxx       Using Engineering Notation in place of the “.”

Engineering Notation Using SI Prefix

Table of engineering notation prefixes.

    Using engineering notation allows for values such as 1,000Ω to be entered as 1K or 1k.  The table above indicates the supported symbols and their meaning.  You can use the symbol in place of the decimal point if you wish.  Do not use both the symbol as a decimal point and a decimal point at the same time.  For instance, the following numbers are valid:

                                                    1k23 = 1,230.0

                                                    1.23K = 1,230.0

                                                    123 m = 0.123

                                                    12µ78 = 0.00001278

    All solutions are given in engineering notation where appropriate.  If you are new to engineering notation, or need to brush up, you may wish to use the Other Multipliers calculator. It allows you to enter a value and see the result in all supported SI exponents.

    Any errant characters entered will cause and error.  For instance, entering 10R0 will not work because “R” is not a valid SI symbol.  This is, however, a valid part marking.  You can decode it using the SMD Resistor Marking ↔︎ Value calculator.

    Where possible, calculations are performed to optimize the result.  For instance, when calculating the resistor values in a voltage divider, all relevant sets of standard values pairs in 5 tolerance bands are used and the optimum value pair for each tolerance is given.  Other calculations, such as filter corners or oscillator frequencies, are optimized as well based on resistor values.  The capacitance values used are those that are commonly available in addition to standard values.  Given the nature of the capacitor market, you must enter the tolerance of the capacitor you expect to use.

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