TPS54335-1A failure on the Bose Solo 5

[rfengg]

Hi there,

My Bose Solo 5 has failed and refuses to switch on.......on  inspection of the main board, it seems that  the TPS54335-1A (10-Pin VSON package) has an internal short between pin 2(PH) and ground 

Has anyone got any experience with this chip? The reviews of the TI part seem pathetic as per the following links.........the 1A version is a revised version of the original TPS54335 but that seems to have many a failure too.
Was wondering if I should bite the bullet and replace the chip only for it to fail in even time or put in an ebay DC-DC buck converter to get the 5V that the TPS54335 is supposed to output? The device dimensions seem too piss-poor to handle 3A IMO.

https://e2e.ti.com/support/tools/simulation-hardware-system-design-tools-group/sim-hw-system-design/f/simulation-hardware-system-design-tools-forum/472649/tps54335-problem-replace-by-tps54335a?tisearch=e2e-sitesearch&keymatch=TPS54335-1A#

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/382644/tps54335-quality-notification?tisearch=e2e-sitesearch&keymatch=TPS54335%2520failure#

[edavid]

I fixed one of these for a friend, and I decided to go with the DC-DC module, since a) I wasn't sure I could get the power pad soldered right on the replacement chip and b) I didn't want to have to fix it again.  So far it's working fine.

The load regulation of the "XM1584" module I used was very poor, so I set it to 5.3V at low load (Bluetooth off), but I'm not sure that was necessary.

If you haven't seen it, here's a helpful repair video:

[rfengg]

Thanks David  .....very interesting video on the same problem that I have been facing......this seems to be the scourge of many a Bose Solo5.
May I know where might be a good place to put in the DC buck converter? There seems to be areas where the main board is relatively sparse but just worried about switching noise coupling noise into the rest of the circuitry.

[rfengg]

David, one more question if I may.......do you know what sort of current is actually supplied by the chip? It it close to the 3A speced?
Still can't understand why a company like TI has "revised" parts failing left, right and center   

[edavid]

May I know where might be a good place to put in the DC buck converter? There seems to be areas where the main board is relatively sparse but just worried about switching noise coupling noise into the rest of the circuitry.

Whoops, I forgot to take a photo, but I think I just stuck it down with double sided tape in the bare spot near the serial number sticker.  No noise problems afterward.

David, one more question if I may.......do you know what sort of current is actually supplied by the chip? It it close to the 3A speced?

It seems to be much less than 3A.

The normal load was around 20mA.  I think the highest I measured was about 100mA, but I wasn't sure what mode of operation would draw the most current, so you might want to measure it in the mode you normally use.

There doesn't seem to be any good reason for the TPS54335A to blow up as often as it does.

[rfengg]

Thanks David 

Was able to fix it yesterday using a MP2307 based Mini 360 Buck converter off Ebay.
Ran the Solo 5 for around 1 hour to make sure nothing was overheating and everything seems fine after the 1 hour test.

Glad I went this route rather than trying to replace the TPS54335-1A; even to take the bloody thing out was a pain......glad I didn't damage the pads though it would not have mattered......I don't think I would have managed to solder another TPS54335-1A  in properly anyways.