Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Total current (A)

Total current entering the parallel pair.

Branch resistance (Ω)

Resistance of the branch whose current is sought.

Other resistance (Ω)

Resistance of the remaining parallel branch.

Compute the current through one branch of two parallel resistances: Ix = It * Rother / (Rx + Rother); the lower-resistance branch carries more current. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Branch current (A)

Current flowing through the selected branch.

• Compact electronics formulas omit some combination of tolerances, temperature drift, bandwidth, loading, parasitics, noise spectrum, nonlinearity, clipping, calibration, layout, and device-specific limits. Typical datasheet values are not guaranteed limits.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

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