Loud noise makers and worker safety

In some workplaces, at some construction sites, there are various machines doing all kinds of things. The issue is taken up in the following Kohler Power Systems presentation (Figure 1) at pages 18 through 25: Figure 1 Kohler Power Systems presentation. The underlying mathematics merits some attention. Imagine two diesel engine driven power generators, two … Read more

Preventing a tarnished reputation caused by partners’ poor performance

Sometimes when a customer has a problem with your product, the blame lies with someone(s) at your company. Maybe, for example, your firm shipped out a smartphone with a cracked display straight from the factory. Maybe it pushed a bad firmware update to users’ routers, bringing down their networks. Or maybe the marketing department went … Read more

Simplify testing of embedded analog-to-digital converters

A few years back, I needed a quick, low-frequency, yet very low distortion source to test an onboard micro-controller ADC to see if it had anywhere near the effective number of bits (ENOB) and linearity that the datasheet said. I knew about the very low distortion, but somewhat complicated design from Linear Technology [1], but … Read more

Low-cost vibration analysis using PC audio and DIY motion sensors

Vibration analysis is a powerful and non-invasive way to measure, understand, and quantify the internal dynamics of mechanical systems, but the cost of the necessary instrumentation is sometimes a deterrent to personal use.  This design idea explores the potential of personal computer audio codecs, software oscilloscopes, and spreadsheet math for acquisition of signals produced by … Read more

Obsolescence by design: The earbuds edition

For well over a decade now, I’ve suffered from right side-dominant back pain. Until the past couple of years, however, the situation was reasonably tolerable. A few times a year, I’d experience intense spasms for a few days straight, which not even prescription painkillers and muscle relaxants would tangibly alleviate. Then the pain would fade … Read more

MEMS mics achieve precise audio capture

A trio of MEMS microphones from Infineon Technologies provides crystal clear audio pickup of the quietest and loudest sounds. Combined with selectable power modes, the high-performance XENSIV IM73A135, IM72D128, and IM69D127 microphones are well-suited for consumer electronics, such as headphones with active noise cancellation, TWS earbuds, and conference devices with beamforming capability. The IM73A135 analog … Read more

Testing Audio Devices

A human ear that is reasonably young and has not suffered too much blasting from high sound levels can detect audio frequencies ranging from about 20 Hz to 20 kHz. Thus this is the range most often used for testing. Modern electronic test equipment can easily produce these frequencies for use as test signal inputs; … Read more

Personal Computer Audio Quality Measurements

This application note presents the audio quality measurements for personal computers. The document discusses the electrical and acoustical performance specifications, as well as test equipment and test set-up details. This application note presents the audio quality measurements for personal computers. The document discusses the electrical and acoustical performance specifications, as well as test equipment and … Read more

Simple Wireless Bluetooth Stereo Audio System

This application note describes how to build a simple and fairly low-cost wireless Bluetooth stereo audio system for outdoor use. The system has 20WRMS output power. It can be controlled either with a handset that has a Bluetooth connection and a music player, or with an Apple® iPod® model. Three appendices discuss additional layout considerations, … Read more

Effective Number of Bits Calculator Tutorial

The Effective Number of Bits Calculator (ENOB) aids in the design and analysis of data converter application circuits. It calculates ENOB, SINAD, resolution, signal bandwidth, oversample rates, DNL, clock jitter, analog noise, and THD. The calculator can be used with a HP 50g calculator or a free PC emulator. Abstract: The Effective Number of Bits … Read more