LED Illumination Provides Constant (Current) Opportunities

 By Jeff Shepard, Darnell Group

What do ac-dc power supplies, lighting ballasts, and driver ICs have in common? They all represent immediate growth opportunities for new designs based on current regulation, specifically for various applications in LED lighting. If you look toward signs, billboards, and specialty applications for color lighting, you'll see growing markets for LEDs.

Create A Simple Crowbar To Protect Prototypes From Supply Overvoltage

 By Sanjay R. Chendvankar, Tata Institute of Fundamental Research

Designers often test prototypes with a variable-voltage bench power supply. If they leave the bench for any length of time, someone may borrow the supply or otherwise change the voltage to a level that could damage components in the prototype. This problem can be prevented by using a variable-voltage "crowbar" circuit connected across the power-supply terminals along with the prototype under test.

 Electronic Design Pop Quiz

Take the “Analoger” Chopper Challenge for your chance to win a free t-shirt and ISL28133 chopper amp samples. Sponsored by Intersil. Test your knowledge now!

Designing With Chopper-Stabilized Operational Amplifiers

 By Don Tuite, Analog & Power Editor

Chopper-stabilized operational amplifiers have been improving in performance and cost advantages, though designers are not always familiar with their benefits. In many designs, these devices can overcome the limitations of offset voltage and 1/f noise found in conventional op amps and be used in applications such as industrial control, medical, and automotive. In this Basics of Design sponsored by Intersil, Electronic Design editor Don Tuite covers the history of choppers and then delves into the details, explaining why these devices make a great addition to a designer's toolbox.

Current-Sense Resistors Handle Overloads And High Temperatures

High overload capability and a wide operating-temperature range mark the Bourns PWR4413 series of through-hole current-sense resistors, which feature 0.8-mm and 1.00-mm terminations and can handle up to 30 A of continuous current and pulses up to 78 A.

Anti-Fuse Element Guards Against LED Open Circuits

Developed to control open defects in LEDs, Murata Electronics North America's anti-fuse device prevents the lowering of power-supply voltage, typically observed in Zener diodes, which results in higher energy efficiency. Other key benefits include a simple and economical circuit design, the reduction of color unevenness, and small size.

High-Voltage Bipolar DACs Drift Minimally

Developed on the company's HPA07 analog CMOS process technology, the 16-bit DAC8734 from Texas Instruments is a four-channel, high-voltage, bipolar digital-to-analog converter (DAC) with up to six times lower drift than competing devices along with the widest operating temperature range and the highest initial accuracy, according to TI.

2-kW DC-DC Converter Accepts Inputs Up To 800 V

Able to generate 2 kW of output power, the HVI 2K dc-dc converter from Absopulse Electronics Ltd. accepts a nominal 600-V dc input voltage (450- to 800-V range). This single-output unit delivers 12 V/130 A, 24 V/80 A or 48 V/40 A, with other outputs available on request.