Donald Boughton, International Rectifier EDN Eliminate errors caused by bias currents and temperature drifts Analog-circuit design often requires a constant-current sink. An example would be for a TRIAC (tri- ode-for-alternating current) dimmer ...
29-01-2012
Part 1 - How does RFID work, Whats stored on the card So the next step was to identify how to pretend to be a card - I wanted a card that I could type a card number into, so it had to have a microprocessor on it, was well as a keypad to allow the ...
28-01-2012
RFID projects have been pretty prominent recently, ranging from projects here in Instructables, to our local Silicon Chip magazine in Australia publishing a RFID door lock project in their November issue. Even I recently purchased a RFID door lock ...
27-01-2012
Martin Tomasz, Sageloop Designs, San Francisco, CA EDN You can combine a carefully chosen op amp, a low-threshold P-channel MOSFET, and two feedback resistors to make a rectifier circuit with less forward drop than a diode (Figure 1). The rectified ...
20-01-2012
On my desktop PC I have a speakers and a headphones. Usually I use headphones, but when I need to switch to speakers I need to physically plug in speakers instead of headphones to my PC’s soundcard. I wanted to solve this problem for a long ...
19-01-2012
Nico Ras, South Africa Project Summary My passion for excellence progressed over the past 40 years to developing sonically superior amplifiers to the highest possible standards, providing life like sound performance. Project Description I am ...
17-01-2012
Charalampos / Haris Andrianakis, Greece Introduction I designed this version in the need of a thermometer for my room, built in a small pack and easy to control. The hardware is designed on a way so that the pcb can be wall mounted. At the top side ...
15-01-2012
Dev Gualtieri When designing with low pin-count microcontrollers, you sometimes need just one or two more digital input pins than you have available. Fortunately, many digital inputs on such microcontrollers also double as low-resolution analog ...
15-01-2012
Part 1 - Features, Schematic and Demonstration Seeeduino Description Seeeduino is Arduino compatible board based on Atmel AVR ATmega328. Its design is based on Diecimila scheme, 100% compatible to its existing program, shield and IDEs. On the ...
11-01-2012
Part 1 Configuring LCD for 8-bit mixed pin mode To make sure things are working correctly lets set up project for 8-bit mixed mode. To do so we connect LCD as follows: Again we uncomment following mode: #define LCD_8BIT_M Then assign pin numbers: ...
31-12-2011
Description A customizable Breathalyzer that talks and tells you how much you’ve had to drink. It’s also open source and can easily be modified with your own text on the LCD screen and audio MP3 files. When tethered to a PC with a USB ...
30-12-2011
Some time ago we have posted alphanumeric AVR-GCC LCD library. It works fine in 8-bit and 4-bit modes. But it has some limitations that some people may find annoying. One of them is requirement that LCD pins has to be byte aligned for instance in 8 ...
28-12-2011
This is the page for the MakerBot watch. It's a portable and fashionable arduino environment that you can take with you. It also tells the time. Specs: Atmel Atmega328 chip with Arduino bootloader on it. 6 pin header for bootloading. Also includes ...
23-12-2011
Part 1 - Reference Hardware Part 2 - ATmega32U4 Firmware, Demonstration Firmware, Windows Applications USB Generic HID C# Communication Library The USB communication and USB specific functionality (such as device attach and detach detection) is ...
21-12-2011
Vladimir Rentyuk, Zaporozhye, Ukraine A magnet waved past a Hall-effect sensor does the trick This circuit allows you to turn on your holiday bulbs with a wave of the magic wand. The strings flash in sequence. At the heart of the idea is the ...
19-12-2011
Bob Zwicker, Analog Devices Many systems must select among two or more low-voltage dc-input sources, such as an ac adapter, a USB (Universal Serial Bus) port, or an onboard battery, for example. You can implement this selection using manual ...
11-12-2011
Part 1 - Reference Hardware ATmega32U4 Firmware The reference firmware is an AVR Studio 5 project which includes both the framework code and the required parts of the LUFA stack. There are two independent firmware types the 'reference firmware' ...
05-12-2011
Sajjad Haidar, Canada The LED and a discrete inductor form an LC tank circuit You can use the inherent capacitance of an LED to make a series resonant boost circuit that can create a voltage large enough to light the LED. Depending on the color of ...
30-11-2011
The following automatic battery-charger design is created with a circuit that could qualify as the simplest window comparator ever built around a single transistor. It starts charging when the battery voltage drops beyond a preset value, and it ...
30-11-2011
Part 1 - Schematic and Firmware Improving the emulator In the previous emulator schematic no inductance value has been defined.To improve the carrier reception - and therefore the reading distance -, the inductance and the capacitance should be ...
27-11-2011
