eagle on Bald Engineer

Five ways to make a schematic (quickly)

Wed, 29 Apr 2015 14:00:37 +0000

Engineers make a schematic to explain their circuits. One time I was looking for a non-tourist pub in Japan. I asked someone for help. She said, “I’m sorry, but I do not speak good English. I will bring my friend, and she will draw you a map.” (Exact quote!) The map her friend drew, gave directions to a bar with a “Neon Yellow Sing.” She meant “sign.”

EAGLE Trivia Challenge: Why the ratnest?

Sun, 05 Jan 2014 12:00:40 +0000

Your challenge, if you chose to accept it, is to determine why EAGLE is showing a ratsnet connection on the far left of the PCB layout. The pads shown with the yellow unrouted line are both GND. They are both surrounded by a ground plane, which is also connected to GND. Hint: it isn’t a bug and it is something many people might ignore by mistake. Can’t figure it out? Or you want to see if you got it? Use a ROT-13 converter for the answer: Gurer vf ab culfvpny pbaarpgvba orgjrra gur tebhaq cynar gung P9 naq 3I3_CJE ner fvggvat ba. Fb juvyr gurl obgu unir n TAQ cynar ninvynoyr, gur cynarf nera’g pbaarpgrq!

EAGLE: Clean up the parts list by disabling libraries

Wed, 27 Nov 2013 12:25:08 +0000

Does it take a few seconds every time you click the “ADD PART” button on EAGLE? Tired of scrolling through an enormous list of parts just to find a capacitor? Here’s how you can reduce the parts listing without deleting a single library. The Control Panel In addition to the usual Schematic and Board windows inside of the EAGLE user interface, there is also a “Control Panel” window. This control panel is typically the first dialog you see when you launch EAGLE. Depending on how your directories are set up, your Control Panel may look like mine when everything except “Libraries” is collapsed.

EAGLE: Using the Add Part's Search

Mon, 18 Nov 2013 06:41:10 +0000

If you are anything like me, your copy of EAGLE has an extensive list of libraries. Most of them probably came with the installer, some which you have added. This, of course, leads to the problem of finding the parts you need when drawing your schematic. Here’s how to use the “Search” box to help. The Problem Here’s what my Add Part screen currently looks like: It’s a mess right? All those libraries, how can I find a single part? That’s where the Search box really play a critical role.

Learn how to use a Mixed Signal Oscilloscope

Tue, 24 Sep 2013 02:15:33 +0000

When I teach the Electronics Measurements class at the TechShop in Austin, I take a lot of pride in showing off the Mixed-Signal Oscilloscope. We have a Rigol DS1102D as well as a standard DSO. To help illustrate the power of the combined digital and analog channels, I created a Mixed Signal Oscilloscope Demo Board, based on a counter, that has an issue that could be turned on or off. This board is also my first time making use of OSH Park’s PCB service.

Minor updates to the Open Source Reflow Oven Project

Tue, 03 Sep 2013 00:06:06 +0000

The next stage of the reflow oven project is moving to a custom PCB for the controller electronics. Overall the board is based on the ATmega32u4 with a DS3231 RTC. The LCD module is intended to be driven by one of Adafruit’s Serial backpacks. There is an area of LED indicators (something I learned from a previous project) and some extra VCC/GND pins sprinkled about. Screenshot of the controller board laid-out.

HackEDA: Collecting and Sharing reusable pieces of electronic designs

Thu, 25 Apr 2013 09:14:56 +0000

One of the most commonly used phrases when writing software is “reusable code.” From the Wikipedia article on “Code Reuse”. Reusable code is: the use of existing software, or software knowledge, to build new software. Software coders have been sharing and re-using code since they first start programming. So why can’t this same idea be applied to hardware design? Doesn’t it seem silly to redraw the ATmega328 for an Arduino based project or even the really simple linear regulator circuit? Well, it can thanks to HackEDA you can start using reusable code to save time (and from creating mistakes).

New Digi-Key tool lets Engineers share schematics - Electronic Products

Fri, 13 Jan 2012 00:33:36 +0000

Tools like National’s (now TI) WebBENCH have allowed engineers to design power supplies without downloading any software for quite some time. Recently I got an account at Upverter.com. This web application is focused schematic capture with social sharing. Just announced this week, Digi-Key is looking to enter this area with their new web based tool to share schematics, Scheme-It(sm). I haven’t had a chance to put it through its paces yet, but I look forward to comparing to Upverter and Eagle version 6 soon.

TLC5940 Painter PCB

Sun, 05 Apr 2009 19:11:09 +0000

TLC5940NT Painter Board This screen shot is an all-layer view of my TLC5940 painter board. The 1st draft featured two TLC5940s, but I decided it made the board too large. Instead, I wanted the ability to mount the painter boards around the LED’s shadow box. This should make routing all the wires much easier. The board is approximately 1.25in x 3.5in. All signals have been routed on the top or bottom layers. Most of the components will mount on (or through) the top layer. Some coupling caps have been put on the bottom. Initially the board had a 7805 built in, to provide +5V to the painter boards and the arduino. Instead, I ripped that out and plan to use the regulator on the arduino instead. There are 6 data and power ports. SER-IN will either come from the host arduino, or from another painter board. SER-OUT contains 2 less pins than SER-IN. I included two surface mount buttons in the layout, so I could get some inputs back to the Arduino, these are entirely option and will only work on a single board.