All posts by Lucky Resistor

Review

Boards in Good Quality from SeeedStudio Fusion

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SeedStudio offered me a coupon to evaluate their PCB service “Fusion“. I am currently working on a new project, so I gave this service a try. I used the following options ordering the two boards:

PCB Dimensions 68mm*108mm
Impedance Control No
Surface Finish HASL Lead Free
Minimum Solder Mask Dam 0.4mm↑
Copper Weight 1oz.
Plated Half-holes / Castellated Holes No
Minimum Drill Hole Size 0.3mm
PCB Color Blue
Base Material FR-4 TG130
No. of Layers 2 layers
PCB Quantity 5
Blind or Buried Vias No
PCB Thickness 1.6
Trace Width / Spacing 6/6 mil

I payed $27.40 for five boards with the option shown above and there were additional $20 shipping costs.

My board design has a very low quality class B4: Minimum drill size is 0.35mm, minimum trace size and spacing is 0.2mm.

Ordering and Shipping

The order process was very simple. The website provides an assistant with all possible options and calculates a quote in real time. I just noticed these minor things:

  • The shipping cost is not displayed in this quote.
  • The dimensions were not correctly extracted from my Gerber files.

The production of the boards and the shipping was quite fast, the whole process only took 10 days until the packet with the boards arrived.

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The boards were well protected in the package, so there were no scratches from the shipping of the boards.

Quality

The boards have a good quality for the chosen options and the price. The alignment of the layers is not perfect, but everything is in an acceptable range.

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The front side of the two boards. Continue reading Boards in Good Quality from SeeedStudio Fusion →

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Projects

Snow Flake Power Converter

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I designed a very simple power converter for the snow flake decoration. The snow flake boards require 3.3V, a voltage which is not commonly available in a household. Therefore the power converter takes 5V USB power and convert it into the required 3.3V.

There is no fancy circuit inside of this box, lazily I simple used a Traco Power TSR2-2433 DC/DC power converter. It is a single component containing everything required. No external components like capacitors or resistors needed.

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Continue reading Snow Flake Power Converter →

Projects

Snow Flake Component Side

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Today I show you a little bit longer video about the assembly of the component side of the snow flake panel.

Compared with the very small 0402 LEDs (1mm x 0.5mm) on the front side, the component side contains just regular 0805 resistors and capacitors.

The first part of the video shows how I apply the solder paste using a metal stencil. I use a system called “eC-stencil-fix” from Eurocircuits. This is basically a set of plates with metal knobs to perfectly align the board with the stencil. With a tick in a checkbox, they produce panels which perfectly work using this stencil fix system, which is really convenient.

Continue reading Snow Flake Component Side →

Common

Perfect Snow Flake Panels from Eurocircuits

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Eurocircuits delivered some perfect panels for the snow flake board. Each panel has five snow flake boards on it.

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This was an impressive good job from from Eurocircuits. There are a quite number of challenges to produce panels in this outstanding quality:

  • The width of the small decorative lines on the front is just 0.15mm. It is hard to get the HAL evenly over the whole surface with lines in all directions like this.
  • White solder mask would show every imperfection. You really can not hide a thing with this colour, it benefits greatly from a clean-room.
  • Milling this board outline is not simple either. You need experience, where to place the bridges to create a stable panel.

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Most vias are tented, which is very nice. These are 0.25mm diameter holes, so it is at the upper limit where tenting works.

I am very happy with the result! The people at Eurociruits have clearly demonstrated their skills and commitment to quality.

Now it will be a real challenge to assemble the board without leaving any marks on the white surface. 🙂

 

Projects

Cat Feeder Device (Quick Build)

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I finished a very simple and quick project recently. It is a programmable cat feeder device. The device is just made for one single portion, but it uses this slide which produces the distinctive sound if the pellets hit the bowl. It is no replacement for the usual feeding of the cat, but some flexible addition to give food out of the regular times.

The whole build was done in roughly four days, using a very quick prototyping and build method.

Design and Build Process

First I had to make a decision about the final size of the device. I used Autodesk Fusion360 to create a model of the device and try to fit all required parts into the device.

Cat Feeder Construction

This is one of the last designs I made until I had the right size. I used a different mechanism as shown here, the important part was to get the right size.

Next I bought plywood in the right sizes for the outer shell of the case. I also got some additional panels fitting inside of the shell for the internal structure.

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I created the shell with four sides, left the top and front side open. To work quickly I fastened the panels with hot glue in place. This has the benefit that you can remove panels using a hot air gun in the prototyping stage.

Continue reading Cat Feeder Device (Quick Build) →

Common, Projects

Plant Watering Sensor Files

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There was a long delay with no update about my projects. The reason for this is, I focused on other non electronic related projects. I promised to publish all files and information about the plant watering sensor project in August, and here are all the files.

First some Important Notes

Even with these files, it is a very advanced project to do. To produce the PCB, you need a board house which is used to precise and high quality PCBs, like Eurocircuits. Also all pads are prepared to reflow soldering, and not hand soldering. It may be possible to solder the resistors in place using a regular solder iron, but it will be hard to do.

Continue reading Plant Watering Sensor Files →