Taranis Q X7: what element U302 is?

[andrewju]

I'm helping to repair a Q7. Initially the problem started with the radio getting stuck on the splash screen (the OpenTX logo). It didn't respond to any key presses after that, even power down didn't work - the battery had to be plugged out to get the radio out of this state.
Also, the radio was recognized as an "unknown device" in Device Manager with no way to install a driver for it.
Ersky9x loaded (via SD card) and seemed to work fine, but no settings were stored ("Bad EEPROM data" message was shown at each boot).

At least one hardware problem is that one leg of the U302 chip and its pad on the mainboard were severely damaged (I would say completely gone).





This is NOT how the radio got out of the factory, of course. The radio owner tried to apply some mods and accidentally spilled some flux (probably some acid...) onto the mainboard.

I tried to solder a tiny wire to the chip in place of that leg. But since it's a TSSOP8 (or something similar), so far I didn't get to a satisfactory result (things are too tiny for this kind of job).




So, actually two questions for now:
- Can this problem (a missing pin) cause all the troubles described above, or should I expect some other failures as well?
- What element this U302 is? The marking is not very clear, and so far I couldn't identify what it really is.

Thanks in advance!

[Kilrah]

It's the EEPROM chip, notably a 24C256 I2C one, probably this one from ST but they're basically standardised so any supplier's one with same package should work as replacement. http://www.st.com/resource/en/datasheet/m24256-br.pdf

The pin that's ripped off is the power supply pin so it's pretty obvious it won't work.

[andrewju]

Thanks a lot, Kilrah!