💡 Getting started
Assembly
Due to the high amount of components integrated in such small PCB layout, most of them are too small to be soldered at home by you. Therefore, these boards come already with the components assembled.
The Smart Dashboard, in addition to the PCB assembled board, consist on the following parts:
An e-paper display. The recommended (and tested working) e-ink panels are the 800×480, 7.5” E-Ink display or the 800×480, 7.3” ACeP 7-Color E-Ink Display. Please note only one display can be connected at the same time and that other displays may not work at all.
A LiPo battery, with a recommended 5000mAh capacity, for space and power. The 6060100 3.7V 5000mAh LiPo battery meets this criteria.
An Dock stand for allocating the electronics + battery + e-paper display.
Optionally, you can mount a solar panel that charges the battery under the right sunny conditions. The output voltage of the panel musn’t excess the 6V.
Powering
The Smart Dashboard is be powered through a LiPo battery plugged into the white JST connector. The voltage of the battery is regulated to the working 3.3V through a low-consumption LDO.
Caution
Connect the battery after clamping the e-paper connector and be careful when plugging it or removing it, since the connector can be hard to plug/unplug.
In order to charge the battery, there is a battery management IC that provides the right charging curve to the LiPo battery and offers a visual indicator (red LED for charging, green LED for standby) while the battery is being charged. There are two ways of charging the Smart Dashboard: USB-C or solar panel.
Solar panel
In addition to the USB-C, and with the aim of extending the service time between (USB) charges of the battery, the Smart Dashboard can be configured to be powered from a solar panel. This feature would imply soldering the solar pannel to the board as indicated in the figure.
USB-C
The USB Type-C is a very extended port for portable electronics, and because of it’s standarized 5V power supply is ideal for charging the Smart Dashboard.
Sensors
As the Smart Dashboard is intended to work during long periods of time without having to be recharged, it is important to avoid undesired consumptions durint the deep-sleep periods. This implies that the sensors have to be powered only when they are needed.
Therefore there is a high-switch circuit that enables/disables the powering of the sensors power line connected to the microcontroller’s output GPIO4.
Regarding the embedded sensors they use the digital bus IIC (\(I^2C\)), which are physically defined with the following pinout:
- SDA
GPIO33
- SCL
GPIO34
Ambient temperature & pressure
The Smart Dashboard embeds an BMP280 temperature and pressure sensor ready to deliver calibrated data through the \(I^2C\) bus.
This sensor has an operational pressure range of 300 up to 1100 hPa ( with a ±1hPa typical accuracy), and a temperature range of -40 to 85 °C (±1 °C typical accuracy)
The \(I^2C\) address is 0x77.
Battery level
For measuring the battery level, the Smart Dashboard integrates the MAX17048 IC.
This sensor measures the voltage of the LiPo cell and does the math to get an estimative percentage of the battery level.
The \(I^2C\) address is 0x36.
E-paper
The Smart Dashboard is capable of driving two different e-paper displays:
However only one can be driven at the same time, since they share the SPI bus pins:
ESP32 |
E-paper |
|---|---|
5 |
BUSY |
6 |
RST |
7 |
DC/MISO |
36 |
CLK |
35 |
DIN/MOSI |
8 |
CS |
Dock stand
The Smart Dashboard PCB can be mounted in a custom Dock stand that you can print on your own 3D printer.