This guide will show how to mount a complete Fuelino board. In order to mount, at home, the Fuelino Proto3, the following components are needed. A soldering station is required to solder the components.
For the complete list, please check the BOM (fuelino_proto3_bom). Schematics and board layout are available here: fuelino_p3_schematic and fuelino_p3_board.
First of all, I mounted the resistors, in order: 3 pcs of 100kOhm, 2 pcs of 1MOhm, 1 pcs of 330 Ohm, 9 pcs of 1.5kOhm.
Then, I proceeded with the diodes: 2 pcs of 5.1V Zener diodes (1N5231), 2 pcs of standard diodes (1N4007), 8 pcs of 12V Zener diodes 1W (BZX85C).
Then, LM339N (comparator) and LM358N (buffer).
The following steps was to mount the small capacitors, 2 pcs of 1uF, 5 pcs of 10pF.
In the following step, I mounted 3 pcs of green connectors, and the LEDs. And also the big capacitor (it stabilizes the 9V power supply).
Then I mounted the connectors for Arduino Nano (15 pins + 15 pins), and also the other small connectors: one UART connector (4 pins), two SPI connectors (6 pins and 7 pins), and one I2C connector (4 pins).
Finally, the last step was to mount the 9V regulator (L7809) and the two MOSFETs (FKI10531).
Actually, the final step was to mount a 1.5kOhm resistor between 5V and A6 pins of the Arduino Nano (to be able to acquire when the battery voltage drops, after key OFF event). I also glued 4 spacers.
Below, the complete board is shown, after mounting an Arduino Nano rev3 on it.
The complete assembly process required about 45 minutes. I recommend to prepare all components in advance, in order to save time and avoid mistakes.