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Reproduction of Raspberry Pi VEAB Controller Hat

In the following documentation, we will show how to reproduce the VEAB controller hat (see below) step-by-step. This board can be produced by hand, but a better and easier alternative is to order it from a PCB manufacturer.

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Step 1: Choosing a PCB manufacturer

There exist a couple of options for suitable PCB manufacturers. One we can recommend is JLCPCB located in Shenzhen, China. There website can be found at https://jlcpcb.com. The manufacturing files of the PCB board comply with this manufacturer. For the following steps, its easier to make an account with the PCB manufacturer.

Step 2: Adding the gerber files

Click on Order now (on the top right). Then add the gerber.zip under ./hardware/board/assembly/. Alt text

Step 3: Setting the PCB options

Once the upload is complete, make sure you have "similar" options. *A minimum of ten boards must be selected to comply for SMT manufacturing. Alternatively, if you wish to solder the boards by hand, the order number does not matter.

Also make sure you select Specify a location under Remove order number

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Step 4: Selecting SMT manufacturing

Once you've selected the PCB setting, we can continue with SMT manufacturing. JLCPCB will not only produce the PCBs but also solder the components for us with this option enabled.

Make sure you have the Top selected for the component placement, and also have Added by customers under Tooling holes. These tooling holes might depend on the PCB manufacturer (1.152mm for JLCPCB), and they assist with the component placement. The gerber files already have these holes on the board, thus no extra manufacturing steps are needed to be taken by JLCPCB.

Press Confirm, and you'll be taken to a new page.

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Step 5: Adding the bill-of-materials (BOM) and footprint placement files

In order for JLCPCB to assemble the board,they need to know which component are required and where they need to be placed. To do so, they require a bill-of-materials and footprint placement file. These files can again be found under ./hardware/board/assembly/; BOM.csv and Footprint_position.csv, respectivly. Add these files, and press Next.

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Step 6: Checking the JLCPCB's parts (in stock)

You'll be greeted with an overview of all the components JLCPCB has in stock. Sometimes, it can happen that these components are not in stock. In most cases, the passive parts like resistors, capacitors, and inductors are in stock; but specialized components like the DACs, ADCs are not. If so, there are two options:

  • Option 1: Find a replacement part that has an identical footprint, value, and property; and replace them in the BOM.csv.
  • Option 2: Continue with the order, and JLCPCB will omit these parts from the assembly. This means you have to order the part elsewhere (i.e., Mouser/Farnell/Digikey) and hand-solder them. (only recommended for those with experience in SMD soldering).

Options for the Digital-Analog converter (MCP4725 -- U3, U4):

  • MCP4725A0T-E/CH -- C144198 (recommended)
  • MCP4725A1T-E/CH -- C61423
  • MCP4726A0T-E/CH -- C191581

Options for the Analog-Digital converter (ADS1013 -- U5, U8):

  • ADS1013IDGSR -- C524815 (recommended)
  • ADS1014IDGST -- C132086
  • ADS1114IDGST -- C206016
  • ADS1015IDGSR -- C193969

Options for the buck-boost converter (SB6286 -- U2):

  • SB6286 -- C157668 (recommended)
  • SX1308 -- C78162
  • SY7208ABC -- C80514
  • AP2008TCER-ADJ -- C130341

Options for the OP-amp (LM358 -- U1, U6, U7, U9):

  • LM358DR2G -- C7950 (recommended)
  • LM358ADR -- C404320

If you wish to choose a different component, make the nessecary changes to BOM.csv under the column LCSC and add the corresponding Cxxxxxx number. In the next step, we will check the placement of these components is correct.

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Step 7: Checking component placement

The next step is crucial -- the component placement. Although JLCPCB will (sometimes) double check any misplacements, it is better to check the placement yourself to be sure. JLCPCB will render the gerber files and the component placement files. Visualizations of bad placements (red boxes) and correct placements (green boxes) are show below. The red dots should match the white dots on the silkscreen. Here, we can see that the orientation of U2,U3, and U4 are off by 180 degrees.

To fix the issue (if they may occur), we can modify the orientation in the Footprint_position.csv which can be done using a simple text editor, or using Excel. Possible orientations are: 0,90,180, and 270; which can be modified under Rotation in the .csv file.

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Step 8: Placing your order

Once all the orientations are correct, press Save to Cart to finalize the order! Its that easy ;)

  • PCB production is 2-3 days,
  • SMT assembly is 3 days

Hence, production time is roughly one week!

Assemble the setup

Required parts:

  • VEAB Controller Hat
  • Raspberry Pi 4
  • I2C extender hat
  • 3D-printed enclosure plates
  • 12V power suply
  • Cables

Assembly

  1. Assemble the base and side plates, the Pi with the I2C hat and the power supply
  2. Fix the VEAB Controller hat on the holding plate
  3. Slide the holding plate into the designated space, fix the holding board to the side plates
  4. Enclose the setup with the remaining plates