E.12Voltage Divider and Standard Resistor Selection

Enter input and target output voltage to find the best resistor pair in the chosen series.

Resistor series

The search covers 0.5–2 times this value. Lower values draw more current; higher values add noise and load sensitivity.

Results

R1 / R2
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Actual output
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Error
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Total resistance
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Current
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Total power
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    Formulas

    Voltage divider
    Vout = Vin · R2 / (R1 + R2)
    Error
    ε = (Vout,actual − Vout,target) / Vout,target

    Note

    R1 is the top (Vin side) and R2 the bottom (ground side) resistor. The result is for an unloaded output; the input resistance of any load appears in parallel with R2. Also account for resistor tolerance (typically 1% for E96) in the total error budget.

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