[time-nuts] MEMS oscillators

Bob kb8tq kb8tq at n1k.org
Tue Oct 30 09:53:30 EDT 2018


Hi

More than sketchy, it sounds a bit crazy. 

MEMS are not a lot different than any IC in that you can get packaging issues. Put them 
in a high pressure “bomb” test and you will see the same issues that you do on any IC. 
The gotcha is that an IC is die coated and a MEMS oscillator  likely is not. They should 
get packaged accordingly (= a low leakage package). 

Getting anything into a package at normal atmospheric pressure … not so much. 

Bob

> On Oct 30, 2018, at 8:44 AM, jimlux <jimlux at earthlink.net> wrote:
> 
> On 10/30/18 3:50 AM, Adrian Godwin wrote:
>> How sensitive to atmospheric environment are MEMs oscillators ?
>> https://www.reddit.com/r/sysadmin/comments/9si6r9/postmortem_mri_disables_every_ios_device_in/
>> It gets closer to time-nuts territory in the earlier discussion - see
>> captaincool's contribution some way down :
>> https://www.reddit.com/r/sysadmin/comments/9mk2o7/mri_disabled_every_ios_device_in_facility/
> 
> The helium leak sounds a bit sketchy, especially when you're talking about a system that has large RF and magnetic fields.  Why would a MEMS resonator care about what gas it is surrounded by.
> 
> That said, I recall someone telling me about problems with early MEMS RF switches and needing some trace amount of water vapor to make them work - work fine on the bench, but them into thermal vacuum testing and after some amount of time they stop working, as the H2O diffuses out of the (non-hermetic) packages.
> 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.




More information about the time-nuts mailing list