Part sourcing assistance - Page 1
Forum section: electronics / general

author: rfleming
author_rank: Regular Contributor
timestamp: May 24, 2022, 03:08:30 am
content: I am not really a fan of doing this type of thing typically and have seen a few other people request similar assistance. So I hope everyone isn't too burnt out on these posts just yet.I am currently working on a physically pretty small project that has way too much criteria and has pushed us into a corner to where we are today. The entire product is a micro, coin cell battery and a couple hall effect sensors. In this case we needed 12 month battery life where the micro wakes up based on a hall effect reading, send a wireless message and goes back into deep sleep.Due to the size constraint and battery requirements, we found our way to the Silicon labs Si7210 series, specifically their DFN packages because they're ~0.4mm in height.Currently we run 3 hall effect sensors, each in different positions to measure trigger mechanisms. In this case each of them is on the same bus. So we are using the:Si7210-B-12-IM2Si7210-B-13-IM2Si7210-B-14-IM2Noting this, we are kind of....screwed...We have attempted to look everywhere we could and reached out far and wide and have been unable to find anyone that has stock. Genuine or otherwise.At this point I am hoping someone may have a suggestion for ways to reach out, websites to follow up on. Or just anyone in general that may have stock of these. I have followed up the only supplier listed on netcomponents though, they mentioned their site was un-updated and they had none.Or finally if anyone may know an alternative that could be used in place of this that would meet the application described above. We have 2 buses available and will likely only need 2 sensors in production, so a single sensor could work and even on a different communication platform, though I2C is preferable.Looking forward to see if someone has that golden arrow.Ryan.

author: Foxxz
author_rank: Regular Contributor
timestamp: May 24, 2022, 03:57:19 am
content: How about something like a AS5510-DWLT or AS5510-DWLM

author: rfleming
author_rank: Regular Contributor
timestamp: May 24, 2022, 04:08:14 am
content: The physical part would work fine, though unfortunately it doesn't have an sleep state where it can wake up, take a measurement and if its higher than a certain threshold, set an output pin to wake the main micro.

author: free_electron
author_rank: Super Contributor
timestamp: May 24, 2022, 04:48:57 am
content: Have you checked skyworks ? Silabs sold an entire division to Skyworks.. maybe the products moved and you are looking under the wrong vendor.

author: rfleming
author_rank: Regular Contributor
timestamp: May 24, 2022, 05:00:27 am
content: Unfortunately it looks like they're very much still si-labshttps://www.silabs.com/sensors/magnetic/si7210Interesting, I looked at skyworks and they some old stuff like tv tuners etc.Closest I found so far was the Bosch BMM150https://www.digikey.com.au/en/products/detail/bosch-sensortec/BMM150/4196671. But it uses 60uA instead of ~6uA. I could do with ~15uA, anything more and I wouldn't reach the 1 year battery criteria. And trust me, the battery size cannot change. Customer also doesn't want a full custom battery.

author: cortex_m0
author_rank: Regular Contributor
timestamp: May 24, 2022, 05:08:52 pm
content: It looks like the different suffixes (-10 to -15) are just different I2C IDs.Mouser reports a few dozen of the SI7120-B-15 in stock, and expected deliveries of the -10, -11, -13 and -15 in June. So hopefully you can deal with different I2C address, and can wait 3-4 weeks and don't need huge quantity.

author: voltsandjolts
author_rank: Unknown
timestamp: May 24, 2022, 05:15:53 pm
content: Just use some standard hall sensors and switch them off. They only take a few us to stabilise. However, your micro would need to wake up periodically to manage this.Alternatively, reed switches are very low power