Electronic Circuits and electronic circuits, electronic schematics plus an extensive resource for hobbyists, inventors and engineers

DiscoverCircuits.com, has 45,000+ electronic circuits, cross-referenced into 500+ categories.
We have searched the web to help you find quick solutions & design ideas.

Got Designs?
Please eMail
if you want me to link to and/or post your original design
NOTE:  We make every effort to link to original material posted by the designer. 
Please contact us if our link is not to your site!  Thanks.


#'s - A       B - C       D - G        H - L       M - P        Q - S        T - U        V - Z

Last Updated: June 02, 2021 01:44 PM

Circuits Designed by Dave Johnson, P.E.

Audio Activated SwitchThis circuit will activate a transistor switch when it detects at least 50mv peak to peak of an audio signal.    It could be used to turn on a relay, routing the signal to were it is needed.. . . Circuit by Dave Johnson P.E.-July, 2006

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 David Johnson P.E.-July, 2000

Automatic DC Motor BrakeIn many DC motor powered systems you would like the motor to quickly come to a full stop.   This circuit provides an automatic electronic braking action to any DC motor ranging from 6v to 24v up to 1 amp of current.  Some of the component values could be changed . . . Hobby Circuit designed by David Johnson P.E.-September, 2004

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

Automatic Room Power Controller -  An ordinary automatic room power control circuit has only one light sensor.  So when a person enters,the room it gets one pulse and the lights come ‘on.’ When the person goes...__ Electronics Projects for You

Automatic Single-Channel Light Dimmer -  It's fully automatic, has a host of features and will drive incandescent lamp loads up to 2400W.__ SiliconChip

Automatic Single-Channel Light Dimmer-Part 2 -  Second   (and final) article has all the construction and setup details.__ SiliconChip

Automatic Speed-Controller for Fans & Coolers -  During summer nights, the temperature is initially quite high.  As time passes, the temperature starts dropping.  Also, after a person falls asleep, the metabolic rate of one’s body decreases.  Thus, initially...__ Electronics Projects for You

Automatic Temperature Controlled Fan -  Here is a circuit through which the speed of a fan can be linearly controlled automatically, depending on the room temperature.  The circuit is highly efficient as it uses thyristors for...__ Electronics Projects for You

Automatic Wash Basin Mirror Lamp Controller -  In restaurants, auditoria and even homes, many a times we forget to switch off the wash basin mirror lamp after use.  The circuit given here automatically switches on the wash basin...__ Electronics Projects for You

Automatic Washbasin Tap Controller -  Make your washbasin tap work automatically when you put your hands just below the water tap outlet.  This infrared-based system detects any interruption of the IR rays by your hands or...__ Electronics Projects for You

Automatic water level controller -  This is simple automatic water level controller circuit.  It will make you more comfortable Because it enables open – close water pump automatically.  When full of water, was ordered off the water.  But When levels gradually reduced To the required, Then turned on fully the water.  So We do not have to worry about overflow and water out anymore.

Automatic Water Pump Controller -  Here’s a circuit that automatically controls the water pump motor.  The motor gets automatically switched on when water in the overhead tank   (OHT) falls below the lower limit.  Similarly, it gets...__ Electronics Projects for You

Automatic Water Tank Filler -  Municipal corporations in many cities supply water during early morning hours.  So, you have to wake up early, just to switch on your motor pump and wait till your water tank is filled up.  Further, there is no control for overflow of the tank.  Many times you come to know of your overflowing tank only when your neighbour informs you.   __ Designed by © EFY Enterprises Pvt. Ltd.

Automatic Bilge Pump Sensor -  This simple circuit will keep your engine bay under control and draws no current while in standby __ Contact: P. Townshend EduTek Ltd

Automatically Switches Off DMM -  08/17/12  EDN-Design Ideas Add automatic-shutoff to your DMM, save batteries, and eliminate wear and tear on the function switch.   Design by Vladimir Oleynik, Moscow, Russia

Automatically Turn Secondary Lamp On or Off -  28-May-09 EDN-Design Ideas A transformer and a relay are all you need to automatically turn a spare lamp on or off Design by Vladimir Oleynik, Moscow, Russia

Automatic-Shutoff Uses Few Components -  07/23/12 EDN-Design Ideas This auto-shutoff circuit uses a bare minimum of components.  You often need to include a timed automatic-turn-off circuit in battery-powered equipment to extend battery life.  Previously published Design Ideas for this function all involve many components   (references 1 through 7).  The circuit in Figure 1 is a simple automatic-shutoff add-on circuit featuring no quiescent current.   Design by Benabadji Noureddine

Automotive 5V Regulator with Cold Crank Capability -  The LTC3115-1 is a high voltage monolithic synchronous buck-boost DC/DC converter.  Its wide 2.7V to 40V input and output voltage ranges make it well suited to a wide variety of automotive and industrial applications.  A proprietary low noise switching algorithm optimizes efficiency with input voltages that are above, below or even equal to the output voltage and ensures seamless transitions between operational modes.  __ Linear Technology/Analog Devices App Note, Dec 5, 2011

Automotive 9V-19.5Vin to 5V at 1A with 60V Transient Protection & 1.7MHz Switching Frequency -  The LT3682 is a 1A monolithic buck switching regulator that accepts input voltages from 3.6V to 36V and transients up to 60V.  It features an adjustable and synchronizable switching frequency from 250kHz to 2.2MHz.  It also has the ability to monitor the current flowing through the external catch diode, thus providing an extra level of protection against output fault conditions over the entire operating frequency range, regardless of input voltage__ Linear Technology/Analog Devices App Note, Jul 22, 2010

Automotive Trafficator -  The last variant on the oscillator is a circuit I built up to replace the standard auto trafficator flasher.   __ Designed by Richard Torrens

Autopilot directs 8255 external buffers -  EDN-Design Ideas 03/03/1997     The PLD in Figure 1 and the corresponding Listing 1 help you change the direction of external buffers connected to an 8255 parallel peripheral interface.  The 8255 integrates three programmable 8-bit ports with handshake and interrupt logic.  In some applications, drive capabilities of the ports are insufficient, and you must add external buffers.  If the data direction is fixed, you can use unidirectional buffers or just strap the control pins of bidirectional buffers.  Even changing the direction of data flow on the fly is no problem, as long as you can afford spare 8255 pins to control the buffers using software. Design by Jerzy R Chrzaszcz, Warsaw University of Technology, Warsaw, Poland

Autotransformer regulator inverts 12V to produce ­12V -  08/01/1997 EDN-Design Ideas You can create a dc/dc regulator with an internal switching MOSFET that inverts 12V to produce an output of 200 mA at ­12V.  The IC is a high-efficiency device whose low quiescent current   (120 µA maximum) is the product of a CMOS process that limits the absolute-maximum input-to-output voltage to 21V.    Design by Dana Davis

Avago Tech Note: Driving & protecting inverter IGBTs -  EDN-Design Ideas 06/12/2014     A special purpose optocoupler can solve your IGBT gate-drive and fault-feedback needs Design 

AVC Automatic Volume Control -  AVC – The featured circuit controls a volume line automatically.  It delivers an output voltage of approximately 4 volts peak to peak.  This voltage remains relatively constant by input voltages ranging from several hundred milivolts to serveral volts.  This electronic circuit is not highly recommended for Hi-Fi __ Designed by Popescu Marian

Avoid pitfalls in dimming & shutting down CCFL backlighting for LCDs -  03/14/96  EDN Technical Article: Providing high-efficiency backlighting for LCDs is easier than it used to be thanks to ICs tailored for the purpose, but several elements of the circuit design still require care.  Dimming and shutdown are two of them.   Design by Jim Williams, EDN's most revered contributor, passed away in June 2011 after a stroke.  He was 63.

AVR Firmware Monitor Program -  Works on AVR controllers with RAM and a hardware UART.  This code is easily modified to integrate with ROM applications to provide the ability to monitor and interact with ROM applications via an terminal simulation program over an RS-232 port.  It can also be used to stimulate and monitor I/O to aid in debugging hardware.  It is very heLPFul to be able to look around at memory, I/O and peripherals, and change things inside a running controller.  If you adapt this to a controller with a stack pointer that is more than 8 bits wide, be sure that both registers in the stack pointer, both spl and sph, are initialized.   __ Designed by Dick Cappels

AVR microcontroller makes improved Motor controller -  10/17/02 EDN-Design Ideas The circuit in Figure 1 provIdeas a novel method of reading the pulse train using an Atmel  (www.atmel.com] AVR processor, from a typical radio-controlled receiver, and to determine the velocity of a motor.  To capture the pulse train from a typical receiver, you need an external interrupt that triggers based on a rising and a falling edge Design by Anthony Di Tommaso, Cranberry Township, PA, and George Simonoff, Petersburg, OH

      <<<         This is last page of #'sA

Control Circuits:   #'s - A       B - C       D - G        H - L       M - P        Q - S        T - U        V - Z

HOME Schematics Index Hobby Corner Dave's Circuits Contact Info
Imagineering Ezine Dave Johnson, P.E. Faraday Touch Switches

 About Us   |  Advertise on DiscoverCircuits.com   |   Report Broken Links  |   Link to DiscoverCircuits.com  |  Privacy Policy

Copyright  January, 1998 - June, 2021     David A. Johnson  All Rights reserved. 

 COPYING any content or graphics to your web site is EXPRESSLY PROHIBITED!