What is the expected voltage drop for the LF side of an XMagic?

[amal]

That’s about all you might expect from lf tune in the xMagic or NExT… I think the most I’ve seen is close to 1000mv drop (1 volt). You’re seeing about 300mv drop, and admittedly that’s a rather small drop… but it is a drop.

You might consider attempting a recovery effort?

Reviving a bricked T5577

The T5577 chip is a great wonder of the world. That said, it is sensitive. The chip’s memory is arranged in blocks, and block 0 is a critical block that holds configuration data for how the chip should behave, if a password is set or not, and other critical settings. It is vulnerable to tearing - the act of leaving writable memory corrupted if the write operation is interrupted or suffers from insufficient power available to complete properly. If you have a T5577 chip based product that appe…