What would cause a XA1110 to stop ACKing I2C?

GPS/GNSS
1

I have a XA1110 GPS module which worked great connected to a Silabs MCU.
But I took the device out to the field and now it won’t ACK the I2C.
I can see the I2C signals are fine and the unit used to work.
The blue LED starts blinking after a few minutes.

I have the unit soldered to my MCU so I can’t easily replace it.

Is there possibility that something changed in the configuration to make it no longer respond to I2C? Looks like the address has only 1 setting (0x10). I only read from it and currently don’t try to configure it at all so it’s running with the defaults which are fine for my application.

2

How many devices are on the i2c bus? Share a photo of the setup/sodlering/wiring

3

Only the XA is on the bus. The pins are soldered via a header. I triple checked the connection and via my scope the XA just doesn’t ACK.
The board has been handled roughly without ESD protection so I suspect it is simply fried. The blue LED comes on and blinks.
I was wondering if there is a config somehow that changed the i2c address or switched to uart or something?
In the mean time I’ve ordered a replacement so I will have to throw this unit away…

4

Alrighty - as a last resort you could try to disable the i2c pull up resistors by desoldering the blob there

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and see if it pops up…if still not, it is probably dead

5

I desoldered the pullups and get:

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So it looks like it is dead. I have replacements coming in today.

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