Hello,
The THVD1420DRLR chip has a pin virtual soldering problem, as shown in the following figure. Solder accumulates at the end of the chip pins, and there is a problem with the cross-section at the end of the pins that cannot be soldered.
Observing the chip body, the following issues were found:
1. The cross-sectional area at the end of the pin shows exposed copper (without tin plating), and there are oblique angled steps.
2. There are obvious stamping marks at the end of the chip pins, causing the bottom of the pins to not be coplanar.
3. The resin encapsulation is higher than the pins (on different sides), causing the pins to not be flat on the PCB surface and forming gaps.
4. Compared with other QFN packaged chips, there are significant differences. The chip pins and resin packaging are coplanar, and the pins can be flat with the PCB surface, so there will be no problem with soldering.
Please help analyze the problem and provide a solution.
