UMW sensors aren't compatible with each other?

[zachliu]

I have this UMW SOP-8 DS18B20 on a pHAT board with external power, the 4.7k pull-up resistor and everything. This chip is likely from DigiKey (not 100% sure though).

I also bought five TO-92 DS18B20A10 from UMW through their direct distribution channel.

Funny thing is whenever I connect the five TO-92 sensors, the onboard one would disappear from the device list.

(almost got consecutive serial numbers here)

But once I remove the TO-92s, the onboard SOP-8 would re-appear 😂

Any ideas?

[cpetrich]

Well, that's somewhat entertaining. I know nothing about SOP-8 chips or the pHAT, I'm afraid. Back in 2019 I had sensors of Family D1 reproducibly disappear when I connected too many of them at once, but never ran into problems with B1 and B2 series sensors. No idea other than I'll try to reproduce this with TO-92s one of these days.

[zachliu]

i'm starting to doubt the authenticity of that SOP-8 chip because i can't trace its exact purchase origin.
also, is the 0223 from its id 28-022367277cff representing manufacture date? if so, it doesn't match with the chip marking 38th week of 2023 🤔