Hi,
We have a board featuring 5 VL6180X sensors and I noticed some oddities regarding the initial offset and scale in the latest production run:
- Some sensors are unable to measure any distance below 15mm
- The ranging linearity between different sensors is +/- 10mm (taken as the delta between a 20mm and a 68mm measurement to a matte aluminium plate).
- Initial offset is varying +/- 10mm
The initial offset appears to be roughly in spec with the datasheet (Table 18. Ranging specification), although we have quite a few sensors at the maximum offset (and in the datasheet this is after 3 reflow cycles, we only have 1).
The linearity is far worse than what I see in "Figure 6. Typical ranging performance".
The largest issue for us is the inability to measure below 15mm. Some sensors simply register 0mm (4 boards out of a batch of 30 had this issue).
I was wondering if this is the expected behavior of the sensors, or if we're doing something wrong in our design/production?
Regards,
Sytse
FYI, our design:
