Soldering TQFN with a distance
The MCBs (Machined Circuit Boards – an alternative to DIY printed circuit boards) are now jumping out from the mini-CNC like in high volume production. This is new revision of RH/Temperature sensor with RS485 interface with Si7013:
New revision of Si7013 sensor module – machined boards
The boards are solder “plated” and prepared for assembly process. However, there is one issue with Si7013. It comes in SMD housing without leads. This is no big trouble, but the thermal pad is, because there is trace routed under the Si7013, which is not GND:
The “problematic” trace is white hatched.
That means it must not be soldered to thermal pad. The good thing is, the thermal pad can be left floating.