Introduction: Portable Power Monitor

By Follow my bilibili：陳亮手痕定律
About: Make it yourself if you cannot buy one ;)

This instructables show how to squeeze a power monitor into a tiny transparent mint box.

Supplies

  1. Jintan Nude Capsule Sugar Free Mint
  2. Digispark Dev board
  3. INA219 Current Sensor Breakout board
  4. 0.96" SSD1306 128x64 OLED breakout board

The mint box and the OLED have different colors, if they can match color should have better result.

Step 1: Power Monitor

This project reuse my previous project Digispark Power Monitor design. It can continous monitor the power usage of a dev device. It can help you develop a portable gadget with expected battery life.

Step 2: Make It Portable

My previous power monitor built on a breadboard, it is not portable enough. So I want to squeeze it in a transparent mint box to save the space and more protection in normal use.

Step 3: Mint Box Patching

We need to cleanup the plastic in the middle of the mint box to free up the space. I just bought an ultrasonic knife, so I try to use this to patch the mint box. Actually use pliers and mini grinder also can do the job.

Step 4: Fit Test

As show in above video, the breakout boards also need some minor patch to fit in the mint box.

Step 5: Soldering Work

Please use thin wires soldering the connection. And also remember use high temperature masking tape to avoid short circuit between the boards.

Here are the connection summary:

Digispark INA219 SSD1306
========= ========= =======
5V -> Vcc, Vin+ -> VCC/VDD
GND -> Gnd -> GND
P0 -> Sda -> SDA
P2 -> Scl -> SCK/SCL

Step 6: Software Preparation

Arduino IDE

Download and install Arduino IDE latest version if not yet:

https://www.arduino.cc/en/software

ATTinyCore

Follow installation step to add ATTinyCore support if not yet:

https://github.com/SpenceKonde/ATTinyCore/blob/v2.0.0-devThis-is-the-head-submit-PRs-against-this/Installation.md

Step 7: Compile & Upload

Please download the source code at GitHub:

https://github.com/moononournation/ATtinyPowerMeter.git

In Arduino IDE:

  1. Open ATtinyPowerMeter.ino
  2. Select Tools menu -> Board -> ATTinyCore -> ATtiny85 (Micronucleus / DigiSpark)
  3. Press Upload button for compile and upload
  4. Wait compile finish and show the "Please plug in the device" message
  5. Plug in the Digispark dev board to upload the program

Step 8: Assembly

Step 9: Enjoy!

Now you can bring along this decent portable gadget with you!