Electronic – Strange Solder Spots on PCB


I was tearing down some old CD drives and while taking a look to the PCB I found two pointy solder spots, connected to the first pin of each side of a chip which makes me think is an EEPROM.

There seems to be no trace connecting to these.

What are they used for ?

Here's a picture :

enter image description here

Other odd shaped pads in the same direction :

enter image description here

Best Answer

These are solder-thieving pads, I think.

This is indeed related to wave soldering process, as @Ignacio had mentioned, but it's not just an indication of travel direction. As the IC travels through the wave, the solder accumulates and it can short the legs towards the end of the IC that enters the wave last. Solder-thieving pads give the excess solder a place to go, which reduces the likelihood that it will build-up and create a short.

Here's a more abstract example (Source)

enter image description here

If these are solder-thieving pads, then every surface-mount IC (at least on that side of the board) should have a pair of odd-shaped pads (all pointing in the same direction).