Here’s a video describing CMOS current sources.
CMOS current source circuits are examined. The voltage versus current and layout are presented. The channel region versus the voltage/current curve is explained. The equation to calculate the Gate-Source voltage is given. The CMOS cascode current source is also explored.
Tsvetan writes to update us on the status of the A20-OLinuXino. They now have their A20-OLinuXino DualCore Cortex-A7 prototypes working fine using Allwinner’s double core A20 which is almost pin to pin compatible with A10.
For more info visit the OLinuXino webpage. General information on the open source software and hardware OLinuXino can be found at Olimex Ltd.
Via the contact form.
An application note from Microchip: Avoiding MOSFET driver overstress (PDF!)
This application note describes how to avoid MOSFET
driver overstress. MOSFET drivers are used in many
applications to drive the high input capacitance of a
power MOSFET device. MOSFET drivers are very reliable when used within their operating specifications.
Care must be taken, however, to control supply line
transients and power dissipation, and prevent latch-up.
Today is National Geek Day! According to Wikipedia,
Geek Pride Day (Spanish: Día del orgullo friki ) is an initiative to promote geek culture, celebrated annually on 25 May. The date was chosen as to commemorate the release of the first Star Wars film, A New Hope on 25 May 1977 (see Star Wars Day), but shares the same date as two other similar fan “holidays”: Towel Day, for fans of The Hitchhiker’s Guide to the Galaxy trilogy by Douglas Adams, and the Glorious 25th of May for fans of Terry Pratchett’s Discworld.
The initiative originated in Spain in 2006 as “Día del Orgullo Friki” and spread around the world via the internet.
What are you doing to celebrate?
Here’s an application note from Atmel on power saving techniques to reduce energy consumption (PDF!):
In this demonstration we will show you how to extend the battery life of our application by multiple factors by modifying only the firmware. You will see that while some of the modifications are very simple and only require setting some registers, other modifications will need some rewriting of the code.
We will use a capacitor as a battery in this demonstration because it is easy to recharge with the same amount of energy. We will use the discharge time as a measure of power consumption.
Here’s a simple Arduino EMF detector by Aaron ALAI:
This is an improved version of an Arduino EMF detector from Aaron ALAI. It uses one resistor and a piece of wire to detect if there is any EMF (elector-magnetic field) around. Nice and simple idea!
Via PCBheaven.
Brohogan presents this post explaining the process for building a solar powered wireless radiation monitor:
This project measures the background radiation outside the house, and transmits it to a display station inside the house. The outside sensing unit is solar powered (but it doesn’t have to be), and should have a range of at least 50m. The display station inside the house continuously displays the current background, and logs it to an SD card (along with date / time, temperature and other data). Daily high counts and other information are also displayed.
Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. More PCBs via Twitter on Tuesday and the blog every Sunday.
Don’t forget there’s free PCBs three times every week:
Continue reading “Free PCB coupon via Facebook to 2 random commenters”
Here’s a summary of major developments over the last week. Free PCB Friday is coming up soon.
Coming up:
Nickjohnson posted an update to his network analyzer we covered previously:
More tweaks and improvements! I’ve moved to a dedicated LED dimming controller for the backlight instead of resistors, and made a few other layout tweaks. It’s now out for fab.
A friend put together some nice renders of the case for me
Via the forum.
Øyvind Dahl writes, “I just hacked a 75 year old radio into an iPhone dock. I used a simple amplifier circuit, parts from an old speaker, an Arduino, some LEDs and a mini dock plug.” You can find more info on the build at Øyvind’s Build Electronic Circuits website.
Via the contact form.
This Alert Tube by Michael Watson monitors the net for events that you choose and alerts you by light patterns, text to speech or sounds:
The Alert Tube is an open source information appliance that connects wirelessly to the Internet of Things in the cloud. The user interface is dead simple, it communicates data via customized colored light sequences, sounds and text to speech. (Check out the video above.)
The idea for the Alert Tube came from something simple, a clock. You don’t have to turn it on, or boot it up and request information, it simply tells you the time, all the time, without you having to ask. That’s the idea behind the Alert Tube. You tell it what you want and then it continuously displays and/or emits audible information, without you having to ask. Simply walk by and take a glance at it or listen for any important alerts. Set it and forget it!
Via Hcked Gadgets.
Moog Engineer Rick Shaich discusses the Ladder Filter, the first Voltage Controlled Filter, which is the heart and soul of the Moog modular synthesizers of the 60s, the Legendary Minimoog of the 70’s, and is still the same filter topology used in all Moog Synthesizers to this day. The Ladder Filter creates the massive, thick sound for which Moog instruments are renowned.
Parallax has revamped their tutorials for learning to program the Propeller in C. You can find a number of programming tips and examples as well as links to the SimpleIDE open source programming tool for use with Propeller C on the Learn.Parallax.C site. For more information on the SimpleIDE download their 33 page PDF User Guide.
It should be noted, however, that the number of C libraries currently available is far fewer than the number of Spin language or Propeller Assembly (PASM) objects available from the Propeller Object Exchange.
Here’s Embedded Lab’s new PIC project: Making a 8×40 LED matrix marquee using shift registers:
This project is about constructing a mono-color LED matrix display board that consists 320 LEDs arranged in 8 rows and 40 columns. The heart of this project is PIC16F1847 microcontroller which receives data from a PC through a serial port (or USB using an USB-UART interface), and display on the LED matrix with the help of five 74HC595 shift registers.
Jadew has been working on a new client for Open Bench Logic Sniffer:
OLSFront is a Logic Analyzer client, currently supporting only the Open Bench Logic Sniffer. At the moment it’s still in alpha so it might have serious bugs and will suffer lots of changes until it will reach beta. It should work on Window XP and above, it’s free, it’s not opensource. The protocol parsers are written in JavaScript so anyone can roll their own. For now the API is undocumented.
Get a Logic Sniffer for $50, with free worldwide shipping.
Via the forum.
Welcome Arduino Yún – the first member of a series of wifi products combining Arduino with Linux:
Massimo Banzi announced it some minutes ago during his annual “The state of Arduino” presentation at Maker Faire Bay Area: Arduino Yún is the first of a revolutionary family of wifi products combining Arduino with Linux.
Yún means “cloud” in chinese language, as the purpose of this board to make it simple to connect to complex web services directly from Arduino.
Philip Peter posted an article describing how he designed his Minimalist AVR programmer:
I always like a challenge, so when I saw [simpleavr]s vusbtiny programmer, I started to wonder how small I could make an AVR programmer. All in all I’m pretty pleased with the result.
The schematic is almost the same as the original one. I only added a LED an resistor to indicate a proper power supply.
Via Electronics Lab.
If you’ve tried to install GNU Radio from binaries without success, this video from NeedSec is for you. He demonstrates how to intall GNU Radio on Kali Linux from source, and confirms operation of the RTL-SDR dongle using GQRX radio receiver software.
Continue reading “Tutorial: Kali Linux with GNU Radio, GQRX and RTL-SDR dongle”
Want a laser engraver for your workshop? Here’s an Instructable by ianmcmill on how to build your own.
If you have some old donated scanners and printers chances are you have most of the stuff needed to make your own DIY Laser Engraver. The main thing that all laser engravers have in common is a method of moving a laser or set of mirrors in an X Y pattern. Scanners and printers have motors and rails that can allow for accurate motion so all that is needed to be added into the mix is a control system, some motor drivers and the laser system. ianmcmill shows us how he did it using an Arduino and 90 € of other various parts.
Via Hacked Gadgets.
