Production Efficiency
Percentage of electronic assemblies that pass all inspection stages without requiring rework or being scrapped constitutes a primary measure of manufacturing health. High line yield indicates that the machine parameters and material quality are correctly aligned with the design requirements.
Process Measurement
Calculation of this figure involves dividing the number of defect-free units by the total number of boards started at the beginning of the process. While first-pass yield tracks the initial success rate, line yield provides a broader view of the total output including recovered units. Monitoring these trends helps identify which specific station, such as the pick and place machine or the reflow oven, is introducing variability.
Data gathered from automated optical inspection is the standard source for these calculations.
Yield Degradation
Environmental factors and component aging influence the stability of this metric over time. If the solder paste exceeds its shelf life or the factory floor humidity deviates from the specified range, the rate of defects typically climbs. Frequent adjustments to machine settings to compensate for poor materials often introduce more errors than they solve.
Stable processes rely on rigorous incoming material inspection to ensure that the baseline yield remains high across different production shifts.
