Update: sometimes pin 1 is right… and still wrong

⚠️ Update on my previous post: sometimes pin 1 is right… and still wrong.

Two weeks ago I wrote:

> "Not every dot on an IC means pin 1."

That story got a follow-up. The pin-1 marking was actually correct.

And yet the ProtoPCBA didn't work after testing.

What turned out to be the issue?

The manufacturer had changed the orientation of the chamfered corner compared to earlier versions of the same component.

So: * ✔ pin-1 according to datasheet: correct * ❌ mechanical reference (chamfer): changed

Result:

A component that looked perfectly placed… but was actually wrong.

Those are the moments when you think again: nothing is what it seems.

But what really counts here: * 👉 that you can patch quickly * 👉 and get straight back to validating

And another good reminder: * 👉 never trust a single reference * 👉 always check your first samples

(Attached: photos of old vs. new component — spot the difference 👇)

Has anyone else run into these kinds of "silent changes" from manufacturers?