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Topic: ATMega changing voltage and clock speed (Read 53 times) previous topic - next topic

threadz

I'm trying to build a device that includes both a ATMega328P and a Raspberry pi that is powered by a LiPo battery connected to Boost converter. The ATMega manages stuff that the raspberry pi can't handle (due to timing requirements or whatever), and the raspberry pi does the bulk of the processing.

One of the features I'm trying to give the device is a software shutdown, where the ATMega disables the Boost converter, turning the raspberry pi and other perennials off. But, the ATMega also runs at 5volts, meaning it would be forced off at this time as well.

So, would it be possible to use a diode to direct power from the battery to the ATMega when the boost converter is off, while still allowing it to run at 16Mhz when the boost converter is on?

Perhaps by switching to an internal clock source or using a clock divider while the boost converter is disabled?

NOTE: I don't want to run the ATMega at 16 Mhz and 3.4 volts the battery will be able to supply (through a diode) I don't want my project to fail randomly due to overclocking complications.

threadz

#1
Apr 19, 2015, 01:17 am Last Edit: Apr 19, 2015, 01:21 am by threadz
I have also considered adding an ATTiny to manage the power supply, BUT my project needs to be compact, so that would require me to completely redo my annoyingly complicated and very dense circuit design.

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