Tool/software:
We have used the TPS63060 successfully on 12 different boards over the years. Recently on one board we are getting a lot of failures in Production.
The board uses the TPS63060 to generate 3.45V to run a radio chip and a frontend module.
Recently the majority of the boards fail testing and require most main parts changed until it eventually works. Costly.
Looking at some rejected modules before any repair work was done, many look the same:
Vfb goes to 0.56V, Vout = 3.6V (I believe either the radio chip or frontend module is going out of operating voltage range and is clamping this from going higher.)
The design has not changed since June 2021, and the TPS63060 part was not changed at that time, so the TPS63060 section remains as designed on the original board revision in August 2016.
We have checked the surrounding components and they seem unchanged and correct.
With Vout = 3.6V, Vfb should be 0.521V but it is 0.56V, as if current is coming out the fb pin.
These came directly from TI, so they should not be bad parts, we assume.
If I apply 3.45V to VOUT and measure VFB they are expected, about 0.5V, and the board draws about 30mA.
I am thinking maybe soldering issues, like too much solder under the body. Yet we have improved our stencil printer/printing and pick and place machines over the years, not degraded them. If anything, we put less solder under the body than we did years ago. Though we didn't have issues before.
The radio chip and frontend modules are not running in the first 150ms or so that I am measuring all this. Bypassing the TPS63060 does not draw lots of current so it does not seem to be a large load messing with things.TPS63060.docx
Suggestions?
