#FreePCB via Twitter to 2 random RTs

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week: Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch […]

E-book reader for the microtouch

Rossum built an e-book reader for the microtouch. He wanted to use the common e-book format epub. But unfortunately since the format is actually a compressed set of text, html links and images, it was too much for the 8-bit microcontroller to handle. To overcome this he developed a transcoding tool (epubgrider) to decompress the […]

Source code for the EvalBotADK USB host driver released under GPL V2

TitanMKD has finished up his USB host driver for Android open accessory on EvalBot. He added an external power supply for host applications that can now draw up to the 500mA specified by the USB standard. He also provided an example of it communicating with the DemoKit. Image by Français: CC BY-SA

Controlling your home over the internet

Maurício developed a Arduino based project for controlling devices in your home over the web. The site is in Portuguese but the video has English captions. The project uses the ethernet shield to allow you to interface with the Arduino over the web, which in return controls relays. How to turn on lights, and various […]

Backwoods logger mini – Open source and on sale

The backwoods logger mini from Big mess o’wires is a thermometer and altimeter for logging your cross country hikes. It is an updated version of the backwoods logger classic. A production test run of pre-assembled units is available for sale. All the PCB files, as well as the source code are available. It measures temperature […]

App note: Understanding switch-mode boost power stages

Boosting DC voltage is required in many applications, like LCD backlight, powering a 5v device with a battery and many more. This app note from Texas Instruments gives a detailed explanation on how it works and how to calculate all your components based on input/output specifications. The report includes detailed steady-stage and small-signal analysis of the boost power […]

App note: Thermocouples, and design guidelines for AD59X TC amplifiers

Analog Devices has an app note on thermocouple basics, and some guidelines on how to design projects with their AD595 and AD594 thermocouple amplifiers. Temperature is the most frequently measured physical parameter. However, the techniques of temperature measurement are grossly misunderstood, often resulting in serious inaccuracies or meaningless data. Thermocouples are basically two wires made […]

App note: Board layout tips for switchmode DC/DC converters

The app note featured here provides basic PCB layout tips for building switch-mode DC/DC converters. As an integral part of their function, switch mode converters have square like signals in some of their traces. These signals create harmonics from the switching frequency that can cause much EMI interference, as well as decreased stability of the converter. […]

App note: DMX512 receiver and transmitter on a PIC

DMX512 is a 3 wire interface protocol used in professional lighting. This app note by Microchip explains all the protocol details and how to implement it on any PIC microcontroller with a hardware UART peripheral. Only external part is a RS485 transceiver. DMX512 transmitter sends 512 8bit data packets one after the other to 512 individual […]

IR protocol decoder software for use with the IR Toy

After we blogged about his IR helicopter automatic altitude control video, amieres added another video. In this one he explains how to decode the IR protocol using a program he developed and the IR Toy. His software has many useful options like frame length recognition with a rounding option to eliminate signal travel time. A replace option is implemented […]

MLX90614ESF IR thermometer interface with the Bus Pirate V3 and V4

TitanMKD shared a demo of the MLX90614ESF IR thermometer interface with the Bus Pirate. His demo contains details on how to read the device specifications in the Bus Pirate I2C mode, ambient and measured object temperature, and PWM mode calibration data. Multiple measurements can be read every 100ms. Via the forum. Get your own handy Bus […]

7400 competition entry: SPI LCD backpack

Stephen added his entry in the Open 7400 Logic competition, he made a LCD backpack that uses the SPI interface. Using two 74LS595 serial to parallel shift registers connected in series, he successfully sends data to the 16×2 LCD and adjusts the backlight brightness, by sending 2 bytes over the SPI. The first byte to be sent is displayed on the LCD, and […]

Free PCB coupon via Facebook to 2 random commenters

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 a every week: Free PCB Sunday. The classic. Every week, […]

PIC LCD backpack free PCB build and hack

Having built a free PIC LCD backpack PCB, Ezflyr decided to hack its pins to use with his temperature and humidity sensor. He successfully adjusted LCD backpack’s firmware, and developed a small app to display the temperature and humidity information on the computer. Via the forum. If you build a free PCB we’ll send you another one! […]

Soldering iron tip selection guide from Hakko

Arhi contacted us about this useful guide for selecting the right size and shape tip for your soldering iron. First part of the article compares various diameter tips used over the same soldering point. Graphs show that for the fastest work-flow is when using larger or same size tips as the solder point. The second […]

Is soldermask required for fine pitch IC soldering?

Intrigued about a discussion on the forum about whether soldermask is needed between fine pitch pads, Brian decided to test it. In the video of the test he placed solder paste on both the FR4 board material, and the soldermask, as well as some on a tined pad. Once done reflowing his results were in. Both the FR4 and the soldermask acted the […]