@friedl_1977, is the HS300x on a breakout? Can you post a picture of your setup?
Hi Peekay.
No, on a custom PCB. Not sure if it will help, but please see picture below:
I am considering buying the evolution board to see whether the code obtained from Github actually works without the mux. It will take about a week to arrive in SA though, so not ideal.
Regards.
@friedl_1977, can you share the schematics or at least the portion showing the HS300x and its connections?
HI -
Sure. Here is die Temp sensor connecting to the MUX.
Based on a previous project (and feedback from manufacturer FAE at the time) additional pull-up’s were omitted due to the 10k pull-up’s on the I2C lines between MUX and uC.
Hope this helps.
Regards, Friedl.
@friedl_1977, the HS300x Vss pin should go to GND directly, not through a capacitor:
Hi Peekay
OH NO!! Could that be it? 
Well, I would say that it’s a problem! You could remove the capacitor and put a solder bridge or a short wire.
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Oh my word… if that is so I would be sssooooooo embarrassed 
Seeing that it is 10.30pm here, I think I will leave the soldering for tomorrow morning. I will revert back and let you know exactly what level of embarrassment I am experiencing then 
Thanks again!!
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Hi Peekay -
Ok, first the good news, please see below
Second I need to apologise for wasting your time with this matter due to a hardware/design issue. The fact that it did not work kept bothering me though as I have implemented this exact design successfully before so I looking into the actual components. On the previous design - and in this schematic, I used 0.1uF capacitor. I measured the capacitor on the board and gave me a 1.0uF reading.
I then checked the components still in the packaging, as I received them from the supplier. They are labeled 0.1uF. 10%, X7R…BUT… multimeter measures them at 1.0F 
I am not sure whether the 0.1uF would have worked or whether it is still wrong, maybe I will test it later today. With such a trivial layout, it is mind baffling to me as to why I would have included the capacitor there if not advised so by the FAE at the time I first implemented the sensor. It was more than three years ago so I do not remember what the reason was, maybe an oversight
Thank you again for you help!!
Regards.
Friedl.
This is not a waste of my time and it's the whole purpose of this community! Besides, many people may benefit from this topic.
So, if I understand correctly, you replaced C16 with a short to GND and found C15 to be a 1.0uF cap instead of a 0.1uF cap, correct?
The cap on VC is a decoupling cap so the larger value may not decouple "as well" but will not stop the device from working. Often in high-speed designs you will see groups of 1uF, 0.1uF and 0.01uF caps used in parallel for decoupling. Each handles a different frequency range of voltage noise.
Besides the missing GND connection to VSS, the real trick with these sensors is the thermal isolation so they don't get warmed by the PCB. As per the datasheet:
If you update the board, you may want to keep this in mind.
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Not quite.
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C15 remains in place, but yes, found it to be 1uF as well as it was from the same supplier. I will make sure this is corrected when the final boards are populated. I threw away the entire batch of passive components I received from them as this is the second time they send me a component with incorrect values to the factor of 10
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C16 was removed and shorted to ground. Device seems to be working as expected, but I still need to double check that the values are indeed correct.
I also contacted the previous client where I used this same sensor. There is indeed a 0.1uF capacitor in place at C16 and according to the client the sensor is functioning. I think what caused me not to even consider this was the fact that the I2C scanner did indeed pick up the sensor and retrieved the correct address.
Thank you for the reminder. These cutouts were implemented on my previous design, but not yet on these prototype boards. I have made a note in Altium so I do not forget
Busy now with the two ToF sensors, VL53L1x is working like a charm. VL53L4x is not sadly. According to the Sparkfun modules they use the same library for both. This does not work in my case on the VL53L4. I found the library by ST but it is quite extensive (44 src files) so was not able to import that into the webIDE. Tried the CLI but it was a disaster, so I am not learning VSC and Workbench 
Just to chime in here too.
As I see it the application note for this sensor would suggest a Vss to be tied to ground directly (no cap) anyhow but the Vdd to be equipped with a parallel cap (which seems missing in your design)
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@ScruffR -
Indeed. I made quite a mess of this one. Thanks for the input!! 
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