ESP8266 Community Forum

- Fri Apr 15, 2016 2:18 am #45510 Lots of great information on the forum here. Thank you. However, I've only been able to find a few bits and pieces so, here are my questions if anyone could spare some time to help

1) Does the NodeMCU v2 have an onboard LM that will accept anything up to 9v on the VIN or is it just 5V ? LM33
2) Could I use a 9V battery (or a battery pack) and a V-23V to 3.3V DC-DC Step-Down buck module?
http://www.ebay.com/itm/2A-DC-5V-23V-to ... 1667714648
Is this the best option?
3) Is anyone familar with using 2 AA batteries and a sleep timer and what type of lifetime do you get from your module. I don't mind changing the batteries once a month if it means an easy/cheap solution

Many thanks

- Fri Apr 15, 2016 2:57 am #45511 For reference, I looked through this rather large thread with many great ideas.
viewtopic.php?f=13&t=577&start=24

I don't know much about power, I'm just hoping to get a couple of months out of the temperature sensor.

Was thinking the the item below is nice and easy for 5V or maybe a 9V battery. Not sure about if it's the most efficient but it looks easy to solder. The other ones mentioned look like chips (SMD?) and much more complicated.
http://www.ebay.com/itm/2A-DC-5V-23V-to ... 1667714648



Any recommendations for an easy sub $5 solution with readily accessible parts (AA, 9V batteries)

- Fri Apr 15, 2016 3:20 am #45512 After a bunch of reading.

I'm thinking to go with a 3 x AA battery pack and a LD1117-3.3 voltage regulator to make sure I don't spike and burn out the ESPP

Will this setup up fully utilize the batteries such as rechargables? I've ready elsewhere that others were getting only 30 minutes on batteries but i'm not clear why.

- Fri Apr 15, 2016 7:49 am #45523 LD1117 is not the best regulator for low power, since it consume a quiescent current of about 10mA.
It is better to use some regulator with lower quiescent current, such HT7333 with about 4uA, or XC6203 with 8uA.