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Digital  / Logic Circuits 
Digital Circuits:   #'s - C       D - G       H - M       N - R       S - T       U - Z

Last Updated on: Wednesday, June 02, 2021 01:44 PM

Circuits Designed by Dave Johnson, P.E.

Audio Frequency Digital Noise GeneratorWhen you need to test an audio circuit with broadband noise, this circuit works great.  It uses just three inexpensive C-MOS ICs that generate a series of output pulses whose widths vary randomly.  I included a level control pot. . . Circuit by Dave Johnson P.E.-July, 2000

Links to electronic circuits, electronic schematics and designs for engineers, hobbyists, students & inventors:

A Quick'n'Easy Digital Slide Scanner -  A simple way to copy slides onto your computer's hard drive.  Do you have a large collection of slides which are deteriorating by the day? Are they growing mouldy or becoming discoloured? Then there is no time to waste.  Get them onto your computer's hard drive before it is too late.  This method is very quick, simple and does not require any electronics.__ SiliconChip

A Remote Telltale for Garage Doors -  If you have a perfect memory you won't need this.  But the rest of us could find it very handy! It lets you know if you've left the garage door open without stumbling out in the dark or the pouring rain...__ SiliconChip

A Rolling Code 4-Channel UHF Remote Control -  It has a long range, its rolling code is virtually unbreakable, it uses a keyring transmitter and it's ideal for use with garage door controllers.__ SiliconChip

A Safe Flash Trigger for Your Digital SLR Camera -  Many of today's digital SLR cameras risk serious damage if used with an external electronic flash, whether that is a portable type or a large studio "strobe".  We found this was the case here at SILICON CHIP so we have produced a flash trigger to ensure the camera's safety.  You can do likewisebut beware of the JISP!__ SiliconChip

A Seriously Bright 20W LED Floodlight -  Last February, we published a DIY 10W LED Floodlight, which has been enormously popular.  We said that one was almost blindingbut to paraphrase Croc Dundee, that's not bright.  THIS one is BRIGHT!__ SiliconChip

A Shielded Loop Antenna for DX AM Reception -  Dramatically improve your AM reception with this tuned loop antenna.  It's just the shot for remote areas & for minimising interference.__ SiliconChip

A Simple Circuit Surface Mount Flash Memory VPP Generator -  DN58 Design Notes__ Linear Technology/Analog Devices

A Sine/Square Wave Oscillator for Your Workbench -  It uses a switched capacitor filter IC to give a very good envelope stability.__ SiliconChip

A 'Smart' Slave Flash Trigger -  Does your camera's flash operate in red-eye reduction    (multiple flash) mode only? This clever unit counts the number of "pre-flashes" before triggering a slave flash unit.__ SiliconChip

A Solar-Powered Intruder Alarm for Sheds & Boats -  Most blokes have got a shedor wish they had! While many people have alarms for their home and cars, a lot of valuable stuff is unprotected in garages and sheds.  It needs protecting and now you can do it with this simple alarm based on a PIR sensor.  It's solar-powered so no mains supply is needed.  And let's not forget boats on mooringsthey need protecting too.__ SiliconChip

A Solar-Powered Lighting SystE - M -  Need lighting away from a power source? Try this one: it's ideal for your garden, shed or even a camp site.  With a 5W solar panel, a 12V SLA battery and a smart controller, it has 3-stage charging for the battery and Maximum Power Point Tracking    (MPPT) for the solar panel.__ SiliconChip

A Solar-Powered Lighting System, Pt.2 -  Last month we described the operation of our new off-grid lighting system, featuring free power courtesy of the sun! Now we move on to the fun part: building it!__ SiliconChip

A Solution Waiting for a ProblE - M -  Think up an application for the Aura Interactor Amplifier and you could win a $200 gift Voucher.__ SiliconChip

A Speed Alarm for Cars; Pt 1 -  Is your license looking a bit a bit dodgey? This compact speed alarm will help you stick to the speed limits.__ SiliconChip

A Speed Controller for Film Projectors -  Do you have old family movies on film? Have you watched them lately? You may be shocked by how much they have deteriorated over the years.  They need to be transferred to DVD before the film deteriorates to the point where it is unwatchable.  Video conversion is not as straightforward as you might think but this simple project enables you to do it.__ SiliconChip

A Stereo Audio Compressor -  Do you hate the way the sound level on your TV suddenly jumps during the advert breaks? Or do you find that the sound levels vary widely when switching between digital TV stations? Or maybe you have problems listening to CDs or MP3s in your car or against the background din during a party? Are the soft parts too soft and the loud parts too loud? This Stereo Compressor will solve that problem.  It reduces the dynamic range of the signal while still maintaining clean sound.  The unit is also ideal for use with PA systems.__ SiliconChip

A 'Tiptronic-Style' Gear Indicator -  It's easy to build and indicates the selected gear in both manual and automatic cars on a digital readout.__ SiliconChip

A Tremolo Unit for Musicians -  Jazz up your music with this easy to build unit.__ SiliconChip

A Universal I/O Board with USB Interface -  This hardware I/O board will let you drive a host of digital and analog I/O    (input/outputs) via the USB interface on your laptop or desktop computer.  Based on an Atmel Atmega32 microprocessor and not much else, it works on Windows, Linux and Macs.__ SiliconChip

A Very Accurate Thermometer/Thermostat -  Based on the very accurate Dallas DS18B20 digital temperature sensor, this thermometer/thermostat provides accurate readings to one decimal point.  The LCD shows current, minimum and maximum temperature readings.  An internal buzzer will sound when temperature limits are exceeded.  It is intended for controlling air conditioners, heaters, cool rooms, wine cellars, etc.  The software is user-customisable.__ SiliconChip

AC Power Line Clock Controller using AT89C2051 -  The Clock Controller V1.1was designed to be an exemplary of using 'C' language to control timer0interrupt, 7-segment LED and keypad scanning.  It provides 1-bit sink currentdriving output, for driving a relay, opto-TRIAC, say.  Many projects requiring7-segment display and keypad interfacing may get the idea from the Clockcircuit and software.   __ Designed by Wichit Sirichote

AC Power Line Voltage Indicator -  The solidstate voltmeter circuit described here indicates the mains voltage with a resolution that is comparable to that of a general-purpose analogue voltmeter.  The status of the mains voltage is available in the form of an LED bar graph__ Electronics Projects for You

Access odd memory locations without hardware -  05/27/99 EDN-Design Ideas Some risc controllers, like the NEC V850 family, use an internal 32-bit architecture with an external 16-bit bus.  The architecture also allows interfaces with 8-bit memories.  HoweverPDF has several circuits, please scroll to find this one.    Design by Sorin Zarnescu, NEC Electronics, Santa Clara, CA

Acquire Images with a Sensor & a Microcontroller -  09/23/10 EDN-Design Ideas Program a microncontroller to process images.   Design by Ioan Ciascai, Technical University of Cluj-Napoca, Cluj-Napoca, Romania, and Liliana Ciascai, Babes-Boylai University, Cluj-Napoca, Romania

ActiveX control brings bit manipulation to Windows -  05/25/00 EDN-Design Ideas Nothing compares with the C language for working with bits.  C provIdeas a rich set of signed and unsigned number formats, along with many intrinsic bit-manipulation operators.  However, most of the popular rapid-application-development Windows languages Design by Steve Hageman, Agilent Technologies, Santa Rosa, CA

Adding external memory to Atmega128. Part 1. Schematic -  Atmel AVR microcontroller Atmega128 is equipped with internal 4Kbytes of SRAM memory.  Is it enough? Well it depends on what project it’s gonna hold.  If your project must deal with loads of data or run larger RTOS code you will definitely run

Adding external memory to Atmega128. Part 2. Software -  To test if external memory board works we are going to write a simple routine that tests if microcontroller can allocate memory heaps, write to and read from then.  First of all we have to set up AVRStudio project.  If your are going to use automated

Addressable DALI Dimming Ballast -  A digitally addressable digital dimming ballast has been developed.  It conforms to DALI standard requiring very few parts and operates at very low power.  Applications include building management or studio lighting where it is desired to control single or groups of lamps for conserving energy, performing lamp maintenance or creating prefect light quality.  The design includes the digital dimming ballast, the code of the micro-controller and a platform to control the ballast by PC.   __ Designed by Cecilia Contenti and Tom Ribarich Applications Engineer, International Rectifier, Lighting Group

Addressable I²C Bus Buffer Provides Capacitance Buffering Live Insertion & Nested Addressing in 2-Wire Bus Systems -  DN329 Design Notes__ Linear Technology/Analog Devices

AFSK 1200 Modem Based on PIC16c620 -  Schematic Only

All-Digital Fires TRIA - C -  07/21/94 EDN-Design Ideas This digital circuit allows a µP to control ac power precisely without using any digital-to-analog circuitry.    Design by Robert Trescott Jr, GTE ImagiTrek, Carlsbad, CA

Alphanumeric LED Display Project -  A phenomenal 256-diode ROM acts as a character generator for a two-digit hexadecimal display.   __ Contact: David Cook

Altimeter Project -  Making a altimeter using the Basic Stamp II.  I finally got my Basic Stamp Pocket Altimeter done.  My first version of my altimeter used a linear equation , which i found is not really accurate at all.  So i got a PAK II math coprocessor to calculate the altitude.  Although the PAK II worked like a charm in my old bulky altimeter, I wanted to make one that was pocket size and the PAK II was just too big.  In pocket altimeter I overcame the Stamp's lack of math capabilties by using a method known as linearization to do the calculations.   __ Designed by Shaun Wilson

An Electric Stethoscope -  Need to do a bit of self-diagnosis? Make sure your heart is still beating or check other body sounds? Maybe you would like to sort out some unusual rattles or other noises in your car's engine or other machinery? This electronic stethoscope will do the job ? and you can listen via headphones or a loudspeaker.  It has switchable frequency shaping in four bands so you can hone in on sounds which might otherwise be masked out.__ SiliconChip

An SD Card Music & Speech Recorder/Player -  This digital recorder stores WAV files on low-cost MMC/SD/SDHC cards.  It can be used as a jukebox, a sound effects player or an expandable "dicta-phone".  You can use it as a free-standing recorder or in conjunction with any Windows, Mac or Linux PC.__ SiliconChip

An Up / Down Digital Counter with 7 Segment LED Displays -  REVISED   Really as Simple as you can get and has 4 Displays __ Designed by G.L. Chemelec

AN-10-002  Miniature power splitters -  AN-10-002 App Note__ MiniCircuits.com

AN31Linear Circuits for Digital Systems -  Linear Technology AN31 __ Designed by Jim WilliamsFeb 2nd, 1989

AN-60-010  Biasing MMIC Amplifiers e.g. ERA SERIES -  AN-60-010 Application Note__ MiniCircuits.com

AN-60-014   New Molded-package MAV Amplifiers  -  AN-60-014 Application Note__ MiniCircuits.com

AN-60-016  MNA, Low Profile, Low Cost, Fully Integrated Monolithic Microwave Amplifiers -  AN-60-016  Application Note __ MiniCircuits.com

AN-60-024   New MAR-8A & MAR-8ASM Amplifiers -  AN-60-024 Application Note__ MiniCircuits.com

AN-60-030  Using the Catalog Specifications to Determine MMIC Reliability -  AN-60-030 Application Note__ MiniCircuits.com

AN7Some Techniques for Direct Digitization of Transducer Outputs -  Linear Technology AN7 __ Designed by Jim WilliamsFeb 1st, 1985

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Digital or Logic Circuits:  #'s - C       D - G       H - M       N - R       S - T       U - Z


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