We are using VL53L0X ToF sensors. Our normal solder assembly process involves ultrasonically cleaning the PCB assembly in liquid. I gather that any kind of liquid immersion can harm the sensor. Is there a recommended way to remove flux residue?

[Zhiyuan.Han]

Hi TCimi

Yes, you concern is totally correct, the liquid will damage the TOF sensor as it is not waterproof design.

To remove flux, my suggestion is you can clean the flux manually with cotton swab dip with flux cleaner.

if there are some dust/smudges on the PCB, you can use a powerful vacuum cleaner to remove them.

Br

Zhiyuan.Han​

[TCimi.1]

Thank you, Zhiyuan.

I'm also worried about flux residue under the ToF sensor which could cause low-impedance between connections. Is there a certain type of solder paste you recommend?

[Zhiyuan.Han]

Hi TCimi

For PCB soldering process, actually you can treat TOF as normal device, just need pay attention to the peak temperature.

I suggest you contact with your PCB solder vendor for solder past question, sorry can't help on this question.

br

Zhiyuan.Han