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Hi developers

You are writing that the Power consumption in sleep mode is 1 mA (without unsoldering R12)
http://z-uno.z-wave.me/technical/

This means that for 1 year you need 8760 mAh battery ... a big one... (*without* any sending/reading)
Even for 6 months it can be a problem...

Unsoldering R12 - where R12 is located? Is it a normal usage case?
What about module warranty - will be Z-Uno replaced without R12?

And - as far as I understand, without R12 it is not more possible to power the Z-Uno from USB, it must be powered all the time from 3.3V input - right?

I have got this question from some users, that's why would like to have here an "official statement"

Michael

ok, ONE question solved (but only this one,...) - have found the location at back side
But not sure, everybody will be able to unsolder at this narrow point the resistor

Michael

> Unsoldering R12 - where R12 is located? Is it a normal usage case?

The location on the photo above is correct. If you want to have a good battery operated device, you should remove R12. But of course your device becomes less convenient to use (don't work on USB anymore, require 3V power).

> What about module warranty - will be Z-Uno replaced without R12?
Officially no, but of course we will consider all cases and will do an RMA if the reason of that RMA is other than removed R12. Of course if you damage your Z-Uno during the removal process (meld plastics or components, put solder in some unwanted place, overheat components around,..) we will not replace it.

We also suggest to just "cut" the component instead of unsoldering it.

> And - as far as I understand, without R12 it is not more possible to power the Z-Uno from USB, it must be powered all the time from 3.3V input - right?

Right!

I asked to recheck the data - my Z-Uno devices have less power consumption:
(without any sensor etc. ...)
- in always listening mode about 35 mA
- in sleep mode about 23 μA

Maybe there is a mistake in technical data?

Michael

What about considering a jumper Bridge for R12 in future hardware revisions?
Would be much more convenient for development...

R12 is for ultimate tunning. Un most cases you will not need it. But we will think about making a jumper. Thanks

Will it still be possible to program the device using USB without R12 (with an additional 3.3V power source connected)?

A jumper would be really great. I think it's a very central feature for Z-Wave devices to consume low power when battery-powered. I've already had fun removing tiny components, it's the number-1 cause-of-death for components for me...

jucs wrote:Will it still be possible to program the device using USB without R12 (with an additional 3.3V power source connected)?

Yes, it is possible.

Anyway while testing and developing the device I would suggest to add a diode (like Schottky) to battery - then you must not remove the R12. Voltage is ok even with diode.
(or you add a small switch parallel to diode - and switch it off while connecting the USB power)

Michael

Thank you for your fast reply! However, I don't understand your advice; how can a diode help me with the power consumption? As far as I know there is no way to get it below 1mA without disconnecting the power regulator by removing R12...

michap wrote:I asked to recheck the data - my Z-Uno devices have less power consumption:
(without any sensor etc. ...)
- in always listening mode about 35 mA
- in sleep mode about 23 μA

This is my experience with 4 different Z-Uno devices - without removing R12.
Please check it while sleeping mode with your Z-Uno

Michael