Here are some of the hardware features:
- 3 channel monitoring, with one of the channels having a "USB C to USB A" power monitor (for monitoring a usb device charging for example)
- ESP32 C3 Mini powered, makes it easy to program and interface with
- USB C interface for programming and power
- Micro SD card support for saving logging data (useful for solar power monitoring projects for example)
- Battey support. Contains all necessary components for safe operation on 3.7V battery (overcurrent, over/under charge, LDO for 3.3V).
- TFT Display and buttons for programable interface. This allows the device to be used without needing a serial connection to a laptop in order to read values.
I am writing the software myself in ArduinoIDE and although the final version is not ready yet. here are some of the software features i'd like it to have:
- Easy to use menu to enable/disable channels, set sampling rates, etc.
- The possibility to use 2 channels together to monitor efficiency of devices (for example monitor the input and output of a 5v boost converter)
- Record accurate date/time and values to a microSD card for later review
- Monitor battery level of the power logger itself and alert when low (maybe send an email or MQTT notification)
- Monitor voltage and current levels on any of the 3 channels and send notifications
- Display a bar graph instead of instant values for the past 1/5/15 min
Hmmm, I love the project and building one similar... just one question though, I'm looking at the datasheet and you have an NPN transistor with the collector tied to EN, the emitter to 3.3V, and the base to ground!?
I see that it's not populated in the picture, but can you please explain why that was put in the schematic to begin with? Was it meant to be used for something at some point, or just an oversight that can be removed??