Hardware Guideline

Overview

This folder contains the NB-Scope nodes hardware designs. Specifically, we have a folder for the mainboard, a folder for all the shieldboard for NB-Scope, and a folder for the auxilliary boards.

Mainboard

The mainboard has 3 versions. Please use ver 3.2. The outdated versions are for reference only. They may work but not very stable. Ver 1.0 and 2.0 are not for NB-Scope projects, thus are omitted.

Shieldboards

We have 7 types of shieldboard designs, supporting up to 9 types of different NB-IoT modules, including:

• Quectel BC28
• Quectel BC35
• Quectel BC26
• Quectel BC66
• Quectel BC95 (Not tested)
• Quectel BG36 (Not tested)
• Quectel BG96
• Gosuncn ME3616
• uBlox SARA-R410M-02B

(Quectel BG36/BG96 and Quectel BC35/BC95, have the same pin assignment, respectively.)

The module PCB project names should be straight-forward in the "Shieldboards" folder.

Auxilliary boards

• Current sensing calibration board
• Firmware upgrade extension board
• Moulde benchmark extension board
• PWR_KEY addon

Libraries

If you encounter missing symbol/footprint problem when opening the schematic or PCB files, please import them in the Libraries folder. The missing libraries should be a subset of the available footprints.

Materials

I put the related documents related to hardware design here, including NB-IoT module summary and various datasheets.

EDA environment

The software to open the projects is KiCad (Pronounced as "key-cad").

PLEASE use the Nightly-build version of KiCad because the projects are created by that. The projects are not backward compatible.

To open the 3D viewer, click "View->3D Viewer" (⌥+3 on Mac or Alt+3 on other operating systems) in the Pcbnew software menu.

If you use the latest version of KiCad to open .sch files, Eeschema, the software component to edit schematic, will ask you to convert the .sch into .kicad_sch. Just go ahead and follow the instruction in KiCad.

You can generate all the files for fabrication in Pcbnew software module in KiCad.

Project structure

• <project_name>.pro: project main file.
• <project_name>.sch or <project_name>.kicad_sch: project schematic design. If .sch and .kicad_sch co-exist, use the .kicad_sch one.
• <project_name>.kicad_pcb: project PCB design.
• Exported Files folder: exported/generated files from the projects, including Gerber files, bill of materials (BOM), positioning files (for SMT process), and other board 3D views or documents. I suggest you double check the project schematic and pcb designs, then generate these fabrication files again by yourself, instead of sending the Gerber files to manufacturers directly.

There are some KiCad generated backup or middle files. I forget to remove them before committing. You may ignore or edit them. They have the following patterns:

• fp-info-cache
• <project name>-cache.lib
• <project name>-rescue.dcm
• <project name>-rescue.lib
• <project name>.kicad_pcb-bak
• <project name>.sch-bak
• sys-lib-table

Click into their corresponding folders for more details

If you have any questions, please send me an email to "yangdeli at msu.edu".