Analog Dialogue: A forum for the exchange of circuits, systems, and software for real-world signal processing.  
 
 

Timely Information

New-Product Briefs:

Recently released products, normally available from stock.

Pre-Release Products:

These front-line products are on their way to being fully released.

Potpourri:

Links to all sorts of "good stuff": Articles, Data Sheets, Patents...

Hot Applications:

The latest from our apps engineers

Latest Print Edition

Editors' Notes   Webinars

Analog Diablog      myAnalog

Analog Dialogue--Since 1967

Analog Devices

Current Feature Articles                Volume 43 — July 2009

Detecting Human Falls with a 3-Axis Digital Accelerometer

Elderly individuals can suffer accidental falls due to weakness or dizziness. The initial injury can be further aggravated if treatment is not obtained within a short time. MEMS-based fall detectors can sense changes in body position by tracking acceleration, determine when an individual is falling, and issue an alert for assistance. This article describes the use of an ADXL345 three-axis digital accelerometer as a fall detector.

Digital Isolator Simplifies USB Isolation in Medical and Industrial Applications

Despite its low speed and point-to-point nature, RS-232 was tolerated in medical and industrial applications because it was universally available, well supported, and allowed easy implementation of the required isolation. The ADuM4160 digital isolator allows simple, inexpensive isolation of full- and low-speed USB peripherals—including the D+ and D– lines—increasing the usefulness of USB in medical and industrial applications.

“Rules of the Road” for High-Speed Differential ADC Drivers

Most modern high-performance ADCs use differential inputs to reject common-mode noise and interference, increase dynamic range by a factor of two, and improve overall performance. ADC drivers—circuits often specifically designed to provide differential signals—perform many important functions including amplitude scaling, single-ended-to-differential conversion, buffering, common-mode offset adjustment, and filtering.

...Recent Feature Articles

Copyright 1995- Analog Devices, Inc. All rights reserved.          ISSN 1552-3284

The Back Burner: Design Ideas, Tutorials, Measurement Techniques

Measuring Noise of Low-Fixed-Gain Differential Amplifiers

Measuring noise of low-gain differential amplifiers presents a challenge, as their integrated feedback and gain resistors preclude high-gain configurations, and a differential-to-single-ended conversion is needed to match the spectrum analyzer. A second amplifier stage can provide gain and the differential-to-SE conversion, neatly solving both of these problems.

Automated Calibration Technique Reduces DAC Offset to Less than 1mV

The AD5360 16-bit, 16-channel DAC is factory trimmed, but an offset of several millivolts can still exist. This idea shows how a simple software algorithm can reduce an unknown offset to less than 1 mV. This technique can be used for factory calibration, or for offset correction at any point in the DAC’s life cycle.

...more Back Burner