What is that and why does it matter?

Backward compatibility is the capability for our customers to take one of our Pb-free products, mount it on their PC board and reflow it using solder containing lead (Pb). ON has conducted reflow tests of Pb-free parts using Pb-containing solder reflow temperatures and processes to simulate this condition. Tests have been conducted at 210 to 230°C and results show that there are no solderability issues. Please note: this does not apply to BGA, bumped die or Flip Chip devices; if the parts are Pb-free they need to use a Pb-free reflow process.

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