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By pcbGuru
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?

By jremington
A better idea would be to use a 3V regulator capable of delivering the required current.
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By pcbGuru
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
This is sufficient for the Appolo
But, as you discovered, insufficient for also charging large capacitors in the required time.
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