snhobbs

Printed Circuit Board Design Resources

App Notes & Blog Posts

The posts from Adafuit: https://blog.adafruit.com/?s=EE+Bookshelf

• System Design and Layout Techniquesfor Noise Reduction in MCU-Based Systems: https://www.nxp.com/docs/en/application-note/AN1259.pdf
• Avoid PC-Layout "Gotchas" in ISM-RF Products: https://pdfserv.maximintegrated.com/en/an/AN4636.pdf
• https://resources.altium.com/p/top-5-pcb-design-guidelines-every-pcb-designer-needs-know
• http://techref.massmind.org/techref/pcbs.htm#bibliography
• https://www.analog.com/media/en/training-seminars/design-handbooks/Basic-Linear-Design/Chapter12.pdf

snhobbs

Device Control

Summary

Search for an easily used interface to a physical device.

Use Case

• Test jig shipped to a CM The dashboard software should be intuitive and simple. Has an interface that allows an operator to use with minimal training. In the case of a test jig sent to a CM this should have a start/stop button and result in a pass/fail reading along with instructions to handle the failed unit. The progress should be available.

snhobbs

Device Control Dashboard

Summary

Read this first: https://github.com/fasouto/awesome-dataviz In the device control discussion the desire for live data and plots from a web interface was discussed. This document discusses the requirements for a web based system for viewing and controlling a device.

Requirements

• Low maintenance cost (stable and small)
• Easily deployed (no complicated licensing)

snhobbs

Designing a Functional Test Stand

Test jigs/stands are devices to aid in the evaluation of a manufactured product. Examples:

• PCBA bed of nails tester & programmer
  • This device would check the integrity of the solder joints and test some of the circuit sub assemblies
  • Complexity increases indefinitely
  • Find issues in parts and production as early as possible, preventing a faulty board being integrated into a more expensive assembly to only fail then.
  • Program parts & nonvolatile memory
• Cable Assembly & harness tester
• Usually a COTS part

snhobbs

Data Acquisition Resources

• MCCDAQ Multiplexing & Sampling
• 8 page pamphlet discussing a wide variety of DAQ systems and introduction to fundementals like the Nyquist frequency, fourier transforms, windowing, and filtering. CONTENTS NOTE: Solid state relays can carry more than 1mA.

snhobbs

[submodule "docker-baseimage-gui"]
	path = docker-baseimage-gui
	url = git@github.com:jlesage/docker-baseimage-gui.git

snhobbs

Methods

Pin Jumper

• Infinite cycles
• Easy access point for test probes

• Jumper can come off a connection
• Large board area
• High loop inductance
• Component cost
• Least Robust

snhobbs

Stackups For Impedance Controlled PCBs

PCBWay

• Materials: https://www.pcbway.com/pcb_prototype/Cost_cores_Foil___Prepreg_for_PCBs.html
• Impedance Calculator: https://www.pcbway.com/pcb_prototype/impedance_calculator.html
• Materials: https://www.pcbway.com/pcb_prototype/PCB_material_classification.html
• Capabilities: https://www.pcbway.com/capabilities.html
• Stackup: https://www.pcbway.com/multi-layer-laminated-structure.html?tdsourcetag=s_pcqq_aiomsg
• Stackup can be customized with an "advanced PCB"
• Checks customer design, changes thickness to comply with impedance level
• 4 Layer boards with 1.5Oz inner copper has 0.22mm PP, 1.0mm core

snhobbs

Embedded Directory Setup

Resources

• https://github.com/TheLartians/ModernCppStarter
• https://api.csswg.org/bikeshed/?force=1&url=https://raw.githubusercontent.com/vector-of-bool/pitchfork/develop/data/spec.bs
• https://github.com/cpp-best-practices/cpp_starter_project

All projects should be able to be built and tested from the top level. This allows for simple building and testing, the same process is followed regardless of project setup. This structure focuses on using CMake and git.

An example of this can be found here.

snhobbs

Custom Parts

• OSHCut [https://app.oshcut.com]: Rudimentory instant quote, bad bulk proce breaks, low cost for low volume.
• Xometry: Have used for CNC milling. Better prices than all other options for brass C360 milling. Job shop broker, has instant quote engine
• Protolabs: Job shop broker
• EMachineshop: Have used for CNC milling. Has own equipment and sends jobs out. No instant quote.
• 3DHubs [https://www.hubs.com/]: Have used for 3D printing. Job shop broker, owned by Protolabs, has instant quote engine. CNC, sheet metal, 3d printing.
• Fractory [https://app.fractory.com]: Job shop broker. Instant quote for laser cutting only. CNC, laser cutting.
• SendCut [https://app.sendcutsend.com]: Have used, low price metal cutting in low quantities. Large selection of materials.

Hardware