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ostaquet / Arduino-Nano-33-IoT-Ultimate-Guide

Arduino Nano 33 IoT - Ultimate guide
MIT License
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About the ultimate power save mode #6

Closed JoshYang1977 closed 3 years ago

JoshYang1977 commented 3 years ago

Hello,

I follow your recommendation and set up the RTC and others with Arduino 33 IoT. When it is implemented, the power only goes through RTC clock (LED in on) but Arduino is not.

If I disconnect the SQW from RTC, both LEDs are on. Do you know what is happening?

Thank you very much for your time and answer.

ostaquet commented 3 years ago

Hi @JoshYang1977,

It seems that your DS3231 is not properly initialized. It is important to setup the registers of the DS3231 before using the power save mode and wake up on interrupt by the DS3231. If not, your Arduino will never be woke up by the interrupt.

KR, Olivier

JAndrassy commented 3 years ago

https://electronics.stackexchange.com/questions/573121/how-can-mosfet-drain-be-used-as-ground-for-a-load

ostaquet commented 3 years ago

Thanks for the feedback @jandrassy, the schematics have been updated based on the advices. The schematic has been simplified and a P-channel MOSFET has been used on the high-side with pull-down resistor to be more sharp on the voltage.