Jesus Echavarria @ jechavarria.com writes:
I develop this MCP23017 Brekout Board to interface a 2×16 LCD display with any microcontroller using a standard I2C bus. Typical 2×16 displays needs at least 6 lines to work (when working in 4-byte mode); in some cases, this will be prohibited for some microcontrollers. With this board, you can control it with only two lines (I2C bus) and, by the same price, obtain a few more IO’s. I use the MCP23017 I2C expander as a bridge. This integrated circuit provides 16 IO’s over a standard I2C bus. All the pins can configure as inputs or outputs independently, and supports high speed I2C (up to 1,7MHz). Also, this device has three hardware address pins that allow connecting up to 8 devices in the same bus. The rest of the features can be seen in the datasheet.
MCP23017 Brekout Board - [Link]
By: Alex Danovich,President San Francisco Circuits
We live in an exciting time where we see a resurgence in electronics as a hobby. Mass production has wiped out a generation or two of kids learning to build radios from scratch with their mom or dad. In the good old days, not sure when, you had companies like Heathkit walk you through building a full size color TV at home, for example. “Yes, I made that!” you’d proudly exclaim to yourself after hours of work.
What’s causing this hobbyist resurgence?
- Television shows such as How it’s Made, Mythbusters and other programming on TLC.
- Websites such as instructables.com, hackaday.com, and specialized hobbyist blogs.
- Interest in RC cars, robotics, gaming, computers etc.
- Advent of Arduino boards, modules and free software.
- Open source software/hardware.
- The whole maker movement in general.
So what does this have to do with making circuit boards? Read the rest of this entry »
Philip designed a simple component size and silkscreen reference board:
since I kept checking old projects to figure out which silkscreens worked, and which didn’t, I made myself a simple reference board. I also included some common SMD component sizes, just to keep me from thinking 0402 was a viable default size.
Simple silkscreen reference board - [Link]
Tom Hausherr’s blog is dealing with component package technology and libraries standards and providing lots of great and clear information. If you are designing your own libraries for your next project you definatelly have to check it out!
Tom Hausherr’s Blog - [Link]
A new PCB design web application was released this last week called PCBWeb. The website states that PCBWeb is a free browser-based CAD application for designing and manufacturing electronics hardware. The tool is currently released in BETA and allows you to create a schematic, full circuit board layout, and then export to gerber format for manufacturing. The application is supported on Windows and Mac using Silverlight.
- Multi-sheet schematics
- Custom Ports
- Digi-Key Part Library (+100K components with symbol and footprints)
- Cut/Copy/Past and full undo/redo
- Multi-layer board
- Support for all units (mm/inch)
- copper pour
- DRC (design rule checking)
- Gerber Export
Bill of Material Manager
- View real-time pricing
- Order Links
PCBWeb – Free Online PCB Design Software - [Link]
Eagle PCB Tip: Pin and Gateswapping
To optimize board routing, there are times that interchanging pins or gates is necessary. Recent article on Dangerous Prototypes gives us a full description and procedure to make this happen in EAGLE.
Eagle Tip: Gateswap and Pinswap tool - [Link]
Surprisingly often, I find myself wanting to import vector images into eagle, and have them appear as polygons – usually for silkscreen. Whilst importing vectors as lines is practical – although ridiculously awkward – up until now I haven’t found a single practical way to import a vector drawing as polygons.
Importing SVG images as polygons Into Eagle - [Link]
Ever want to print your own PCBs for high power LEDs, other SMT power devices, but regular PCBs can’t sink enough heat? Fear no more! You can print them right onto silicone thermal tape!
PCBs on thermal tape – Put them on heat sinks! - [Link]
Many users often request if there are any tools that can simplify library part creation. Make-symbol-device-package-bsdl.ulp is one of those tools, it can parse a BSDL file and automatically create a part for you, device, symbol, package everything in just a few clicks. It’s one of the more sophisticated ULPs that ship with EAGLE and can be used to speed up part creation especially with high-pin count components such as FPGA and large microcontrollers. Most manufacturers such as TI and Microchip provide BSDL files for their parts. This is also one of two ULPs that come with a manual you can find it in the doc folder of your EAGLE installation. [via]
Eagle Quick Tip: Simplify library part creation - [Link]