LNK302DG gives me another voltage

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Hello everyone,

I designed a circuit and made a prototype in a perfboard and all works good (around 5.4V output consuming 0.25W)

When i received FR4 PCB design, it doesn`t work properly (only gives 3.4V output consuming 1.1W, then the IC arrive huge temperatures after some seconds)

Both circuits (prototype and FR4 PCB) have the same schematics, but different LAYOUT.

I am attaching schematics and LAYOUT used.

Please give me support.

첨부 파일Size
schematic34.86 KB
layout174.49 KB

I am adding in this review that inductor must to have 1mH, with that the output is giving me 4.8V but i need around 5.4 like in the prototype.

Could be this be caused for max rating voltage of C2 (BP Capacitor) that should be 50V (like AN-37 says) ?