White-LED Driver Touts High Efficiency - 12-Jun-03 EDN-Design Ideas White LEDs, the most recent addition to the LCD backlight, find common use in providing backlight for color LCDs. Thanks to their size and white-light output, they appear in small, portable devices with color displays, such as PDAs and cellular phones. Like other LEDs, a white LED needs a constant-current source—typically, on the order of 15 to 20 mA Design by Dimitry Goder, Sipex Corp, San Jose, CA
White-LED flasher operates from one cell - 05/26/05 EDN-Design Ideas 1.5V circuit flashes white LED Design by Anthony H Smith, Scitech, Biddenham, England
Why Limit Your Power Supply's Input Range? - 20-Mar-03 EDN-Design Ideas Multilayer capacitor doubles as varactor-Taking only a cursory look at the input-voltage ratings of your power-supply IC can limit the usable input-voltage range. With careful examination of an IC's operating specifications and circuit topology, you may be able to work around that input-voltage limitation. For instance, The data sheet for TI's (www.ti.com) TPS61042 shows that it has all the functions necessary for providing a constant-current drive to a white-LED circuit; however, the input voltage of the IC does not meet the input-voltage requirements of this Design Idea. The dual lithium-ion input voltage varies from 6 to 8.4V, but the TPS61042 input-voltage range is 1.8 to 6V. Design by Michael Day, Texas Instruments, Dallas, TX
Wideband AGC has 60-dB dynamic input rang - 10/10/96 EDN-Design Ideas Automatic-gain-control(AGC] circuits serve in many applications to maintain signals at fixed levels. However, in applications such as digital-receiver circuits and back-channel modems, the function of the AGC often aims more at increasing dynamic input range through the controlled application of both gain and attenuation. In this type of application, the AGC is usually upstream of a high-speed ADC. The Design by Carl Dickey, National Semiconductor, Comlinear Division
Wideband Oxygen Sensor Controller Mk.2, Pt.1 - Accurately measure air/fuel ratios with an improved oxygen sensor__ SiliconChip
Wideband Oxygen Sensor Controller Mk.2, Pt.2 - Last month, we introduced our new Wideband Oxygen Sensor Controller Mk.2 and described the circuit. This month, we give the circuit for the display unit and the full construction details.__ SiliconChip
Wig/Wag LED Flasher - This simple circuit will flash two LEDs in an alternating fashion. . . Circuit by Dave Johnson P.E.-December, 2004
Wind Direction & AirFlow Measurement - The LTC2990 is used to monitor system temperatures, voltages and currents. Through the I2C serial interface, the device can be configured to measure many combinations of internal temperature, remote temperature, remote voltage, remote current and internal VCC. The internal 10ppm/°C reference minimizes the number of supporting __ Linear Technology/Analog Devices App Note, Mar 16th 2011
Windshield Wiper Delay - The intermittent wiper circuit shown above causes the auto's windshield wipers to wipe once every several seconds instead of constantly wiping. The circuit may be added to older cars to provide the intermittent function or it __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Wiper Speed Control - A continuously working wiper in a car may prove to be a nuisance, especially when it is not raining heavily. By using the circuit described here one can vary sweeping rate of the wiper from once a second to once in ten seconds
Wire Loss Compensation using a Current Referenced LDO - This circuit shows a cable drop compensation circuit using a current referenced regulator, the LT3080. A precision 10μA set current, ISET, is sourced through two series connected resistors to program the output voltage for the remote load. To compensate for the load connecting cable drop requires sourcing an additional __ Linear Technology/Analog Devices App Note, Jun 19th 2013
Wireless LED Flasher - There are times when you would like to flash a LED through a thick plastic case without wires. The circuit below performs this feat. It can be powered from a supply ranging from 3v to 6v. It draws about 300ua of average current at 5v. . . Circuit by David A. Johnson P.E.-January, 2011
Wireless Remote Control for Raymarine ST4000 Autopilot - uses raytheon's seatalk®communications protocol. (16f628) __ Designed by Jon Fick
Wireless Remote Controller Receiver - Schematic Only __ Designed by Jon Fick
Wireless Remote Controller Transmitter - Schematic Only __ Designed by Jon Fick
Wireless RF PWM Dual Motor Controller - This is a very simple Wireless RF transmitter circuit that consists of the Holtek HT-12E encoder chip and AM 418MHZ-transmitter module (WZ-X01, other similar device can be used). Using the hybrid RF xmit/receive modules make building the RF remote control a lot easy __ Contact: info @ wzmicro.com
Wireless Stepper Motor Controllers - Here is a low-cost and simple wireless stepper motor controller using infrared signals. Using this circuit you can control the stepper motor from a distance of up to four metres. The circuit...__ Electronics Projects for You
Wireless Volume Control - 17-Aug-11 -Design News: Andrew Morris decided the usual wireless volume controls don’t offer enough functionality, so he created the ultimate volume control that connects between a computer or MP3 player and an amplified speaker system. __ Andrew R. Morris, Gadget Freak-Case #192
Working with Stepper Motors - We've all experimented with small "hobby motors", or free-spinning DC motors.
Stepper motor driver that will allow you to precisely control a
unipolar stepper motor through your computer's parallel port. With a
stepper motor you can build a lot of interesting gadgets such as
robots, elevator, PCB drilling mill, camera panning system,
automatic fish feeder, etc. If you have never worked with stepper
motors before you will surely have a lot of fun with this project.
Xenon flash valve - An experiment of the xenon flash valve. __ Designed by The Electronic Lives Manufacturing-presented Chan
Xenon Flasher - You are going to like this project. It costs less than $3.00, contains six BUILDING BLOCKS, re-cycles a disposable flash camera and you are going to learn a lot about electronics.
Everyone has seen a disposable flash camera. __ Designed by Collin Mitchell
Xenon Lamp Flash Detector Amplifier - This circuit has a very low standby current requirement yet has very high sensitivity toward the light flashes from a xenon lamp. When connected to a flip/flop it can serve as an on on/off Controller. . . Circuit by David Johnson P.E.-December, 2004
Xenon Photoflash Controller - This 9v battery powered circuit is designed for remote control flash needs. A charge control circuit turns off the high voltage generator when the photoflash capacitor is fully charged. A neon lamp is included to indicate when the system is ready to flash. . . Circuit by David Johnson P.E.-June, 2000
Xenon Strobe Light - A xenon flash tube is a triggered gas discharge device. A voltage may be impressed across the tube and it will not conduct until the xenon gas is ionised by an external high voltage (typically 3 to 5kV). Once triggered, the gas becomes a very low impedance, and discharges the storage capacitors in about 1ms (this varies considerably, but this figure is fine for basic calculations) __ Designed by Rod Elliott ESP
Xenon Strobe Light - Disco anyone? Actually, this strobe serves a much more useful purpose then making it look cool when you dance in the dark. You can use it to view fast moving objects, look for craks in PC boards (hold the strobe on the trace side of the board and look from the component side) , and it is a great attention getter in a store window __ Designed by Aaron Cake
Xenon-9 Speed Controller - The FET speed controller is made up of several smaller blocks, each which is quite easy to understand. The R. C. transmitter sends control information to the receiver as a string of width modulated pulses. The receiver sorts these out __ Contact: Collin Mitchell
Xmas Lights Tester - Like every year around the same time, I hurried to get my Christmas tree all set up and the first thing we do when the tree is 'standing' we like to hang the lights in the tree. Okay, better first test them before putting all 50 of them in the tree. Yep! Working beautifully. I started a carefully planned organization of the lights so they would be evenly divided over the branches. Now the second string of lights, tested, yep working. In the tree with them. Putting the plugs into the receptacle andoh no-- one series of them are on in full glory, all the others are out. Annoyed I tried to 'fix them' by trying to push each bulb further into their sockets. Still no go __ Designed by Jan Hamer
Yellow Light of Death: PS3 Repair - Revive your PS3 console from a system shutdown. __ Contact: Jameco Electronics
Zener-basedType 1 (Voltage Controlled) Solar Engine - This design uses a Zener diode to determine the voltage trip level. Simple variants of this design use LEDs or plain old diodes in series to accomplish the same thing. __ Designed by Wilf Rigter |