AN4159

Software

Doc ID 023639 Rev 3

23/27

Case 10:

“Does the hole in the LPS331AP need to be covered for a post machine solder wash cycle?

Does ST ship the parts with taped coverings?”

●

No need to use any tape to cover the hole on CAP of LPS331AP during reflow. The

cleaning of the PCB is not general (it’s only cleaned when the PCB is contaminated

during reflow). The LPS331AP pressure sensor is not covered.

Case 11:

“What are the soldering and processing guidelines for the LPS331AP pressure sensor chip?

No wash?”

●

Please find reflow profile (Pb-free) IPC JEDEC standard here. There are no particular

processing guidelines for the pressure sensor. The key things to remember are:

–

To place the pressure sensor at the edge of the pcb where warping is minimal.

–

There should be no cleaning process performed on the pressure sensors

Figure 9.

High temperature lead-free soldering profile 260 °C max

Figure 10.

Example of solder machine profile