ESP8266 Community Forum

- Thu Feb 05, 2015 11:51 am #9065

can you share your schematic? TPS73633 seems very usefull

I don't have any
typical app for this IC (SOT23-5)
pin 1(IN) to accu (or via some R for measurement voltage/current/power on INA219)
pin 3(EN) to IN via some R ina my case 4,7k
pin 2(GND) to ESP-05 GND
pin 5(OUT) to ESP-05 VCC3V3
pin 4(NR) NC
that's all - i2c devices connected directly to GND/VCC3V3 and SDA/SCL to ESP8266 URXD/UTXD

of course don't forget about some big capacitor close to ESP8266

MY GITHUB: https://github.com/reaper7/

SDM Energy Meter: https://github.com/reaper7/SDM_Energy_Meter
MLEDScroll (TM1640 led matrix): https://github.com/reaper7/MLEDScroll

- Thu Feb 05, 2015 1:23 pm #9077

Is there a clear winner product for this scenario?

I guess a clear winner would be something like the LTC3113. This is a combined buck-boost regulator, which can provide a stable 3.3V output with an input voltage from 1.8V-5.5V with a quiescence current of about 50uA.
But it's quite expensive and even the TSSOP package has to be reflowed, so it's impractical for most hobbyists.
The LDO reaper7 suggested is probably the best & cheapest solution, but you should test how the LDO behaves if the input voltage drops below 3.4V.

- Thu Feb 05, 2015 2:49 pm #9090 A lot depends on what thingy.

A pair of AA or AAA batteries can be used if the thingy isn't on much.

A AAA battery lasts several hours for an average application, depending on temperature and rate of discharge [pdf] and the lowest voltage at which the ESP8266 can operate with the radio on.

For my button thingy, that works out to around a few thousand presses of the button, which I find acceptable.

For a sensor that has to report regularly, it is a no-go.

ESP8266 for dummies, LuaLoader and project updates: http://benlo.com/esp8266

- Fri Feb 13, 2015 6:06 am #9631 Thank for all your replies. I will look into them and find one to suit me.