ESP8266 Community Forum

- Fri Feb 06, 2015 11:26 pm #9155 Hey all,

I am working on a motion anklet and am considering using the ESP8266-03 board to transmit 4-5 bytes at a time (once a minute at most). An arduino will process motion data and if data corresponds to a triggered pattern, data will be sent. The anklet will be using the following components:

Arduino Micro (5V)
1200 mAh Battery (3.7V, 500mA max discharge rate)
3.3V 300mA Linear Voltage Regulator
Adafruit 9-DOF IMU

I have heard/read that the Arduino Micro can't supply enough current during peak power consumption. I am thinking of connecting the battery to the voltage regulator and powering the ESP8266-03 module that way. Is that the most sensible solution for powering the both the arduino and the WIFI module?

I appreciate the help!

- Sun Feb 08, 2015 5:25 am #9229 A few of things to look out for:

Assuming that you are using a lithium battery, the voltage will range from 4.1v or so when fully charged, to 2.9v when fully discharged. The load must be disconnected when the voltage goes below 2.9 or you risk permenant damage to the battery. The esp8266's ADC might be used to detect this.

Common linear regulators require that the input voltage be at least 0.7 volts above the output voltage, so with a 3.7 volt you'd likely have problems. So called low dropout regulators are available and would overcome this.

A possible solution would be to do away with the regulator, and just put a diode in series between the battery and the esp; the diode voltage drop of 0.7v will give you 3.4v to 2.2v, which the esp should cope with.

Let us know how you go.

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