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Electronic, PC, Microprocessor &  Mircro Controller based Kits & Projects for School &  College level students

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18 Bit ADC uses PC's Serial Port - 09/27/01 - EDN-Design Ideas:  A PC usually requires a plug-in ADC card to process analog signals. However, with  circuitry in Figure 1, a PC can communicate with an 18-bit ADC through its serial port.  port provides both positive and negative power supplies as well as control signals. IC1 is an 18-bit MAX132 ADC with a serial interface. / (schematic)
25-Pin PC Serial Port to MIDI Synthesizer Interface Cable - (electronic circuit)
27MHz USB Dongle - (application / block diagram)
9 to 9 Pin Female Null Modem Cable - (Tony van Roon's circuit / schematic design)
9-Pin PC Serial Port to MIDI Synthesizer Interface Cable
A Practical Guide to Cable Selection - National Semiconductor Application Note  (app note)
A Serial Infrared Remote Controller - (electronic circuit)
Accurate USB 2.0 temperature Sensorneeds only a handful of parts - 05/24/07 - EDN-Design Ideas:  A USB-to-serial converter forms the heart of an accurate USB temperature sensor.....(design idea)
Add Current Boost to a USB Charger - 09/19/02 - EDN-Design Ideas:  The popular USB interface can charge a portable device while transferring data. But for high-capacity batteries,  500-mA output current of USB hosts and powered hubs greatly extends  charging time. (Unpowered USB hubs supply no more than 100 mA.)Thus, a system that accepts charging power from an ac adapter as well as.....(design idea)
Advanced Topology USB Battery Charger Optimizes Power Utilization for Faster Charging - DN336  Design Notes (Linear Technology) (app note)
An Adjustable Video Cable Equalizer using the LT1256 - DN92  Design Notes (Linear Technology) (app note)
An Introduction to USB Descriptors: With a Gameport to USB Gamepad Translator Example - Microchip Application Note Published 4-May-04  (app note)
AN1003: USB Mass Storage Deviceusing a PIC MCU - Microchip Application Note Published 30-Aug-05  (app note)
AN-1088: LVDS Signal Quality: Cable Drive Measurements using Eye Patterns Test Report #3 - National Semiconductor Application Note  (app note)
AN-1347: PCB Layout Techniques for Adaptive Cable Equalizers - National Semiconductor Application Note  (app note)
AN240 EP9312 USB Version 1.1 Slave Reference Schematic - (app note)
AN255 Populating the USB Components on the EDB9301 Development Board - (app note)
AN258: Low Cost USB Microcontroller Programmer the Building of the Pickit™ 1 Flash Starter Kit - Microchip Application Note Published 7-Jul-03  (app note)
AN-916: A Practical Guide to Cable Selection - National Semiconductor Application Note  (app note)
AN950: Power Management for PIC18 USB Microcontrollers with Nanowatt Technology - Microchip Application Note Published 19-Nov-04  (app note)
AN956: Migrating Applications to USB from RS-232 UART with Minimal Impact on PC Software - Microchip Application Note Published 3-Dec-04  (app note)
AN971: USB Port-Powered Li-ION/Li-Polymer Battery Charging - Microchip Application Note Published 31-Jan-05  (app note)
APC Back Pro UPS cable - ….(circuit design)
APC Dumb UPS cable (simple) - ….(design added)
APC Smart UPS cable - ….(circuit design)
APC Smart UPS interface port - ….(electronic schematic)
Apple Mac to MIDI Synthesizer Interface Cable - (electronic circuit)
AVR In-System-Programmer - USB AVR programmer that supports a lot of AVR microcontrollers.….(circuit design)
Bit Wacker - 18F2550  - This is an easy to assemble, through-hole version of the popular UBW board. This is a spectacular little development board featuring the PIC18F2550. Based on the work of Brian Schmalz, the UBW is a small board with a command interpreter for basic input and output control. When attached to a Windows/Max OS X/Linux computer, the UBW will show up as an RS232 Com port! You control the individual I/O pins on the PIC through simple serial commands. This is a kit and includes a pre-programmed 18F2550 and both male and female connectors so you can choose which connector you would prefer. ….(design)
Bit Whacker - Simple input / output device - The UBW board is a small board that contains a Microchip PIC USB-capable microcontroller, headers to bring out all of the PICs signal lines (to a breadboard for example), only costs about $15-$20 to build and is powered from the USB connection. I designed this board to be a simple parallel port replacement tool for Bruce Shapiro for use in his bits-to-bytes-to-bots class. Apologies to all other 'Whacker' projects like EDTP's Packet Whacker for stealing a great name . All tools used to design this project are free, and the design is open to anyone to use for whatever they wish. Please build your own and improve upon it! ….(design)
Build a UPS for USB devices - 04/11/02 - EDN-Design Ideas:  Portable systems often include circuitry that derives power from an external source, such as USB. When  system disconnects from  USB supply, a battery takes over and supplies current via a dc/dc converter. A diode-OR connection (Figure 1)offers  easiest way to ensure that  supply voltage doesn't sag during this switchover to  battery.
Build a USB based GPIB controller - 12/16/05 - EDN-Design Ideas:  Roll-your-own USB-based instrumentation bus.....(design idea)
Cable Finder Seeks Out Wall Conduits
05/11/00 - EDN-Design Ideas:  (design idea)
Cable Tester - (electronic design)
Casio QV-200 Digital Camera Cable.  - Lose your cable? Build it yourself and save $29. Fits many QV models.
Centronics Port Generates Narrow Pulse Widths - 08/02/01 - EDN-Design Ideas:  Variable-pulse-width signals are useful in control circuitry for positioning and holding purposes in robotics and power electronics. Frequently,  need arises for pulses with width less than 1 msec. Delays less than 1 msec are usually not available in most programming languages, so generating such pulses can be a problem
Circuit charges supercapacitors to 7V from USB power - 04/26/07 - EDN-Design Ideas:  Switching regulator charges three supercapacitors with current limit
Circuit compensates system offset of a load cell based balance - 08/16/07 - EDN-Design Ideas:  A dual DAC stores the system-offset voltage, which gets determined during a power-on calibration sequence)
Color Video Travels on twisted Pair Cable - 08/17/95 - EDN-Design Ideas:  This circuit transmits video anywhere phone lines exist. Although the circuit has more electronic components than the traditional single amplifier used to drive a coax cable, you can easily justify the additional electronics required to drive twisted-pair cables)
Commonly Used RS-232 Serial Port Cables
Connect  RS232 modem to E-10G - Here is the instructions to build a cable adaptor  to  connect your pocket PC with any external  RS232  modem. The Pocket PC must have serial  port.….(electronic schematic)
Connecting Sega 3d Glasses to a PC Serial Port - (circuit / schematic)
Control stepping motor via USB interface
Current-Limited DC/DC Converter Simplifies USB Power Supplies - DN252  Design Notes (Linear Technology) (app note)
Data acquisition system captures 16 bit voltage measurements using the USB - 05/25/06 - EDN-Design Ideas:  USB interface simplifies PC-based data capture system.....(design idea)
Data acquisition with PIC18F4550 - This project is simple and small component count USB data acquisition or USB DAQ. The main core of USB device is PIC18F4550 .The firmware for PIC modified from Microchip CDC library. When connect this USB Data acquisition with PC then windows ask for driver after driver installed(only first time) you will have a new COMx if not connect the COMx not create by Windows. ….(circuit design)
Demonstrating the Soft Detach Function: With a PS/2ฎ to USB Translator Example - Microchip Application Note Published 4-May-04  (app note)
Designing USB 2.0 Interface using PI3USB20 Switch - Pericom Semiconductor Application Note # 067 (app note)
Drawing Power from a PC Serial Port - This circuits derives fairly low power, (mA at5V) from a RS-232 serial connection. (NOTE: ASCIII drawing)
DS1820 PC Thermometer - This is a digital thermometer based on USB PIC16C745 microcontroller from Microchip and DS1820 sensor from Dallas Semiconductor. Temperature readings are sent over USB port in HIDCOMM USB mode to VB6 program on a PC. Hex program and sample Visual Basic 6 application is included. ….(circuit design)
DSerial RS232 cable - This is a simple cable to connect your DSerial to any other device with an RS232 port.  (circuit)
Dual Voltage Regulator meets USB Power needs - 08/19/04 - EDN-Design Ideas:  This Design Idea stems from the limited availability of IC voltage regulators that can meet key USB-power specs, coupled with the need for turn-on sequencing and rise-time control at each output. As always, for PC-related designs, minimum cost is a primary motivation. USB specs require all loads to limit inrush current to less than 100 mA plus 50 ตC of charge when powered.....(design idea)
Dynamic siphon steals current from USB port - 12/15/06 - EDN-Design Ideas:  (design idea)Make maximum use of a USB port's current-delivery capability.
Efficient All-In-One USB Power Management IC Solution - DN1008  Design Notes (Linear Technology)  (app note)
Firmware Library Errata - Microchip Application Note Published 18-Aug-05  (app note)
Flash Drive - (application / block diagram)
FT232 USB Interface Adapter - Control up to three devices from a PC with FT232 IC (USB to Serial UART) from Future Technology Devices International FTDI. Circuit is simple and does not require external microcontroller or any type of firmware programming. PC control software written in VB6 is included. ….(electronic schematic)
General purpose components implement USB based data acquisition system - 06/26/08 - EDN-Design Ideas:  A serial ADC communicates with a PC's USB port through a serial-to-parallel converter and a USB-interface IC.....(design idea)
Hardened Ethernet cable goes underground - 02/02/06 - EDN-Design Ideas:  How to environmentally "harden" a Category 5 UTP(unshielded-twisted-pair)cable.....(design idea)
Hi-Fi USB Audio DAC - Regulator: This board supplies DAC board with +/- 15V for analog section. MUR860 in rectifier bridge, LM317 and Lm337 as regulator IC's and BG-STD at the output. LM317, LM337 power supply PCM2702: A little modified version of ....(circuit)
Hi-Fi USB Audio DAC with PCM2702  - The heart of this circuit is low-cost 16-bit Philips DAC. As a SPDIF decoder was chosen Cirrus Logic CS8412 IC with SN75179 as an input driver....(circuit)
Hints and Kinks for USB Decoding - 05/07/02 - EDN-Design Ideas:  The USB is a serial data-transmission system that uses cables to connect peripheral equipment to PCs. All new computers have two or more USB receptacles, and the predictions are that they will replace most of the legacy receptacles on older PCs. The 1.0 and 1.1 standards for USB were for 1.5 and 12 Mbps at lowand full-speed rates, respectively.....(design idea)
How to Construct Garmin GPS Receiver Interface Cables - (electronic circuit)
How-to build an USB device with 18F4550 or 18F2550 - (project)
I/O interface board for PC - (electronic circuit)
IgorPlug-USB (AVR) Universal USB interface - Yes!!! now its possible to connect an AVR  microcontroller direct to USB port of PC, running  windows. This circuit is infrared (IR) receiver.….(design)
Interface Cable for Casio Qv-200 Digital Camera - Lose your cable? Build it yourself and save $29. Fits many QV models. (electronic circuit)
Interface MIDI instruments to a PC through a USB port - 04/17/08 - EDN-Design Ideas:  You can interface MIDI-equipped musical instruments to a PC via a USB port.....(design idea)
iPOD Charger - The circuit's pretty simple, basicly it's just a voltage regulator. Both the LM317 and the REG1117A (LDO) fit the PCB, maybe there are even more types that I'm aware of that can be used on it. I did add one extra thing: a LED that shows if the connected device is consuming power. To do this I used a shunt resistor and a current converter. I choose 0.2 ohm for the shunt, since it's not hard to come by and should only drop 0.1V @ 500mA. Either an INA168 (current output) or an INA193-198 (INA194 is best in this case) (voltage output) will fit as current converter. The trip point at which the LED should start to burn can easily be adjusted by one resistor (in case of the INA168) or by two (in case of the INA193-198). In the schematic it is set at 100mA using an INA168 using a 950k resistor. The Schmit buffer is a Texas Instruments Little Logic chip (1G17). ….(electronic schematic)
Laptop Computer Serial Port Power Booster - (schematic / circuit design)
LCD 2 USB - LCD2USB is a open source/open hardware project. The goal of LCD2USB is to connect HD44780 based text LCD displays to various PCs via USB. LCD2USB was meant to be cheap and to be made of easily available parts. It is therefore based on the Atmel AVR Mega8 CPU and does not require any difficult to obtain parts like separate USB controllers and the like. ….(circuit design)
LED Light - A simply and easy-to-make circuit, useful when working with the computer at night. (6/08/2006)
LED Load - The board supports driving two separate tri-color LEDs. More can be setup inline if desired. Currently the software only uses the second LED and its color represents the CPU load of the system in real-time. Blue for idle and gradients light blue, green, yellow, orange, and finally red indicating heavy CPU utilization. If the system fails to respond, the LED begins flashing RED to indicate a lack of communication from the software. This lets you easily identify a crashed machine in a rack for example. ….(design)
Link Neatly Measures Temperature - 10/26/00 - EDN-Design Ideas:.....(design idea)
LM1823 High Quality TV Video I.F. Amplifier and Synchronous Detector for Cable Receivers - National Semiconductor Application Note 09 Apr1996 / (app note)
Low Cost USB Microcontroller Programmer the Building of the Pickit™ 1 Flash Starter Kit - Microchip Application Note Published 7-Jul-03  (app note)
LVDS Signal Quality - National Semiconductor Application Note  (app note)
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