Design Ideas: Circuit schematics, applications, software, videos contributed by electronic engineers from EDN

Read the latest Design Ideas

Illumination ring provides focused intensities

William Grill, Honeywell Aerospace, Olathe, KS; Edited by Martin Rowe and Fran Granville --EDN, 7/9/2009
Light up an area for optical inspection using LEDs under PWM control.

Digital variable resistor compensates voltage regulator

Jason Andrews, Maxim Integrated Products Inc, Dallas, TX; Edited by Martin Rowe and Fran Granville --EDN, 7/9/2009
A look-up table compensates for temperature drift.

Hot-swap switch provides easy thermal protection

Donald Schelle, National Semiconductor Corp, Santa Clara, CA; Edited by Martin Rowe and Fran Granville --EDN, 7/9/2009
Remove power from your circuit when things get too hot.

Add headphones to a Class D amplifier

Hiroshi Fukushima, Technical Research Center, D&M Holdings Inc, Kawasaki City, Kanagawa, Japan; Edited by Martin Rowe and Fran Granville --EDN, 7/9/2009
Connect headphones to the MAX9704 and make a quieter lab or office.

Circuit eases power-sequence testing

Goh Ban Hok, Infineon Technologies Asia Pacific Ltd, Singapore; Edited by Martin Rowe and Fran Granville --EDN, 7/9/2009
A low-cost design controls power-up of two power sources.

Create a swept-sine function in LabView with just one virtual instrument

Sean McPeak, University of California—San Diego; Edited by Martin Rowe and Fran Granville --EDN, 6/25/2009

Charlieplexing at high duty cycle

Luke Sangalli, Digital Designs, Melbourne, Australia; Edited by Martin Rowe and Fran Granville --EDN, 6/25/2009

Serial port tests digital circuits

Yury Magda, Cherkassy, Ukraine; Edited by Martin Rowe and Fran Granville --EDN, 6/25/2009

DAC calibrates 4- to 20-mA output current

Ronald Moradkhan and Steven Lau, Maxim Integrated Products, Sunnyvale, CA; Edited by Martin Rowe and Fran Granville --EDN, 6/25/2009
When your design requires self-calibration, this circuit will perform the task.

Alarm tells you to close the refrigerator door

Boris Khaykin, TRW Automotive, Livonia, MI; Edited by Martin Rowe and Fran Granville --EDN, 6/25/2009
A simple gadget that you place inside the refrigerator alerts you by beeping if the door stays open for 20 seconds or longer.

Fast 10-line-to-one-line data selector/multiplexer comprises only two ICs

Marián Štofka, Slovak University of Technology, Bratislava, Slovakia; Edited by Martin Rowe and Fran Granville --EDN, 6/11/2009

Implement a simple digital-serial NRZ data-recovery algorithm in an FPGA

Jef Thoné and Bob Puers, ESAT-MICAS, Katholieke Universiteit Leuven, Leuven, Belgium; Edited by Martin Rowe and Fran Granville --EDN, 6/11/2009
A shift register and some logic lets you recover embedded clocks from data streams.

LED strobe has independent delay and duration

Michael C Page, Chelmsford, MA; Edited by Martin Rowe and Fran Granville --EDN, 6/11/2009
High-brightness LEDs, with independent delay and duration, find use in a visual-inspection application.

Cancel sensor-wiring error with bias-current modulation

W Stephen Woodward, Chapel Hill, NC; Edited by Martin Rowe and Fran Granville --EDN, 6/11/2009
This circuit cancels the wiring-resistance error inherent in diode temperature sensors and requires only two conductors in the sensor cable.

Simple FSK modulator enables data transmission over low-speed link

Israel Schleicher, Prescott Valley, AZ; Edited by Martin Rowe and Fran Granville --EDN, 6/11/2009
Send digital data over a low-speed link.

Current-sense monitor and MOSFET boost output current

Gyula Diószegi and János Nagy, Divelex Ltd, Budapest, Hungary; Edited by Martin Rowe and Fran Granville --EDN, 5/28/2009
You can bypass BDC current-settings resistors and use a MOSFET to increase current.

Multiplexed, programmable-gain, track-and-hold amplifier has instrumentation inputs

W Stephen Woodward, Chapel Hill, NC; Edited by Martin Rowe and Fran Granville --EDN, 5/28/2009
This ADC front end implements the standard ensemble of functions.

Simple circuit smoothly drives stepper motors

Uwe Schüler, Institute of Physiology, Tübingen, Germany; Edited by Martin Rowe and Fran Granville --EDN, 5/28/2009

Excel spreadsheet yields RLC best-fit calculator

Alexander Bell, PhD, Infosoft International Inc, New York, NY; Edited by Martin Rowe and Fran Granville --EDN, 5/28/2009
Excel lets you automate engineering functions to find best-fit values of resistors, inductors, and capacitors.

Automatically turn secondary lamp on or off

Vladimir Oleynik, Moscow, Russia; Edited by Martin Rowe and Fran Granville --EDN, 5/28/2009
A transformer and a relay are all you need to automatically turn a spare lamp on or off.

Top Next >>

Design Ideas

Search Design Ideas