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Hi,

From the "about Z-Uno" page:
DC-DC installed:
7–18 V → 5 V: NCP1117ST50T3G, max current sourcing from 5V pin 900 mA
5 V → 3 V: MCP1700, max current sourcing from 3V pin 200 mA

Does it mean that there is no voltage regulation on the 3.3v pin?

What is the range of voltage the 3.3v pin can take?

I am looking to power Z-Uno using Batteries (and perhaps even monitoring the same batteries using the Z-Uno ADC pins). I'm wondering what type of batteries can work with this 3.3v pin without additional voltage stepup hardware?

Option 1. 3V Button cell eg CR2450 which can barely provide 3V?
Option 2. 1S LiPo which is 4.2V (fully charged) to 3.7V (Empty)?
Option 3. 2x 1.5V Alkali AA batteries or 3x 1.2V NiMH AAA batteries?
Will any of these work? Which is better?

Thanks for your feedback!

Z-Uno will work from 2.8 to 3.6 V. No need to monitor the battery via ADC pin, as Z-Uno will automatically report you battery level based on Vcc voltage

CR2450 is ok. But max current is pretty low.
3.7-4.2 V is too much
2x AA is perfect
3x1.2 will be ok if it is not more than 1.2 (not more than 3.6 in total)

PoltoS wrote:Z-Uno will work from 2.8 to 3.6 V. No need to monitor the battery via ADC pin, as Z-Uno will automatically report you battery level based on Vcc voltage

CR2450 is ok. But max current is pretty low.
3.7-4.2 V is too much
2x AA is perfect
3x1.2 will be ok if it is not more than 1.2 (not more than 3.6 in total)

Awesome information! Thanks!

Be careful with NiMh - the voltage is > 1.2V!
Only the nominal voltage is 1.2V, but fresh batteries have higher value - up to 1.4V !!

as sample. http://data.energizer.com/PDFs/nh15-2300.pdf

Michael

PoltoS wrote:Z-Uno will work from 2.8 to 3.6 V. No need to monitor the battery via ADC pin, as Z-Uno will automatically report you battery level based on Vcc voltage

CR2450 is ok. But max current is pretty low.
3.7-4.2 V is too much
2x AA is perfect
3x1.2 will be ok if it is not more than 1.2 (not more than 3.6 in total)

Hi,

What's the voltage that triggers Z-Uno to report the low battery level? I powered the Z-Uno with 2x fresh AA batteries but it died after 3 days without any triggering.

(I would have set the mode to FiLR but it would have made my ZUNO_SWITCH_BINARY not functional according to the other thread in this forum...)

On ALWAYS_LISTENING Z-Uno will live about 2-3 days only. And it will not even report the presense of batteries as it is not assumed that always listening mode will run on a battery.