MEP EP#4: Linear Effects of Licensing

Parker Dillmann |   |  Engineering, FX Dev Board, MEP, Podcast, SAIM

MacroFab Engineering Podcast

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Download: MP3
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Hosts:
Parker Dillmann
Stephen Kraig

Guests:
NaN


Figure 1: SAIM Frame. Work in Progress.

Figure 2: The Guitar FX Development Board

Podcast Notes

  • Audio quality of the podcast leveled up! Stephen and Parker went over to The Pharmacy Recording Studio which is run by Josh Moore. He hooked them up with 2 (!) microphones and an acoustically pleasing room. Big thanks to Josh!
  • Parker has been working on the X-Y Platform which has been code named the SAIM which stands for Semi-Automatic Inspection Machine. Half of Parker’s job is coming up with “cool” acronyms.
  • The SAIM will be a PCB inspection machine for low volume runs at MacroFab. See Figure 1.
  • Parker gets Open Beam and Open Builds confused again. Similar names and similar products! Parker is using Open Builds V-Slot Linear Rails for the SAIM.
  • Controlling the SAIM is the Macro PLC. It is a in house designed CNC controller based off the Parallax Propeller.
  • Stephen has been working on the FX Development board. This board has all the power supplies and trimmings you need to develop guitar pedals, analog effects, and synthesizer circuits. The board has two solder-less breadboards as well built in. See Figure 2 for the prototype.
  • This week Stephen and Parker have not been able to work on the Super Simple Power Supply (SSPS) but will be getting back to that project next week. Getting a solid cooling solution down is the next step.
  • Selling 3D objects that you did not design? Ethically or Morally wrong? Depends on the license.
  • Mouser’s website verse Digi-key’s website. Stephen really likes how clean Mouser’s website and attribute searching works. Parker likes Digi-key’s pictures as they make it easier for shopping for connectors and switches.
  • Parker suggests reading the errata datasheets first before picking a microcontroller.

Special thanks to whixr over at Tymkrs for the intro and outro theme!

  • Henrik Sandaker Palm

    I went back and listened to old episodes, I have now reached the end of the podcast and have to wait a whole week between each episode, which is sad.

    But one thing I remember from all the old episodes which I could not manage to forget is the discussion of Mouser vs. Digikey parametric search. I’ve always thought Mousers ability to correctly label parts parameters is hair-pullingly bad compared to Digikey. Let me take one example from just now, which I think is exactly how it feels each time I browse mouser for parts.

    I needed to see all SOT23-6 boost converters with maximum output voltage above 34V, adjustable or not.
    After choosing circuit type and package, mouser left me with 4 values above 34 V to choose from:
    35 V
    38 V
    5 to 36 V
    adj.

    This again left me with four different parts each with one of those output values. Fine, I thought, here I have four parts, two with fixed output voltage, and two with adjustable voltage output. One of the adjustable ones have a secret output voltage. The truth is that all of them are adjustable, and if you were wondering about any of their minimum set output voltages, they are secret too, except for the “5 to 36 V”-part (my point is this should be split into two parameters).

    The “adj.”-part had a maximum output voltage of 5.5 V so now I’m down to three parts.

    The “38 V” part, however, is really a 27 V part, because Mouser choose the “SW Pin Voltage”-value from the “ABSOLUTE MAXIMUM RATINGS”-table instead of the “Output Voltage”-parameter under Electrical Characteristics. Bear in mind that “SW Pin Voltage”-value is the maximum voltage the internal mosfet switch can see, it does not mean you can actually produce 38V on this pin.

    https://uploads.disquscdn.com/images/955f3ac4f587ae96ae632e3e57820d5b2d1fd39dd08138f9b64d27b1b6de885b.png