SparkFun Forums 

Where electronics enthusiasts find answers.

Everything with the AmbiqSuite SDK tools and software are welcome here.
User avatar
By pcbGuru
#229188
Hello,
We power the Apollo 3 MCU with 3V regulator. Upon turning board power on it takes 5ms for the power to go to 3V. Is there a requirement that the MCU power voltage reaches 3V in 1 ms.
We suspect that a slow power rampup is causing brown out.

Is there a way to disable the brown out detector?

Thanks
By jremington
#229190
A better idea would be to use a 3V regulator capable of delivering the required current.
User avatar
By pcbGuru
#229191
Our regulator has the following spec "Current - Output 80mA"
This is sufficient for the Appolo. I just tried removing some capacitors in the MCU voltage path. I noticed that previously the MCU power voltage would reach 3V in about 5ms. After removing large caps it reaches 3V in 2ms. After this the MCU resets after power cycle as expected. Seems to have solved the problem.
By jremington
#229221
This is sufficient for the Appolo
But, as you discovered, insufficient for also charging large capacitors in the required time.
 Topic permissions

You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

long long title how many chars? lets see 123 ok more? yes 60

We have created lots of YouTube videos just so you can achieve [...]

Another post test yes yes yes or no, maybe ni? :-/

The best flat phpBB theme around. Period. Fine craftmanship and [...]

Do you need a super MOD? Well here it is. chew on this

All you need is right here. Content tag, SEO, listing, Pizza and spaghetti [...]

Lasagna on me this time ok? I got plenty of cash

this should be fantastic. but what about links,images, bbcodes etc etc? [...]