Stacked Tolerance

The cumulative effect of multiple component tolerances combining across a circuit or system. When several components each carry their own tolerance, the real-world output can deviate significantly from design intent. That's not because any single part is out of spec, but because all their individual variations add together. In a PEMF pulse circuit, stacked tolerances across the timing capacitor, drive resistor, coil inductance, and switching transistor can shift the actual pulse width, peak current, and field strength well outside the expected range. Worst-case stacked tolerance analysis identifies the maximum possible deviation by assuming every component simultaneously sits at its worst allowable extreme.