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ESR

What does ESR mean in a BOM?

The small internal resistance of a capacitor that limits ripple current and causes heating. ESR decides whether one capacitor can replace another in a power supply, so it is checked before a cross-reference is accepted.

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Every part on your BOM, resolved automatically.

O2 reads a bill of materials end to end: it normalizes part numbers, checks lifecycle and compliance on every line, finds alternates, and drafts the quote.