EEWeb Articles

Capacitive Coupling to Human Body

2013-05-22T15:00:03-07:00

Introduction to BodyCom Technology utilizing the BodyCom Development Kit demonstration. Microchip’s BodyCom™ Technology is a short-range, low-data-rate communication solution for securely connecting to a wide range of wireless applications.

Avoid Design Misinterpretations

2013-05-22T14:44:50-07:00

Abstract: Humans are unusual creatures because sometimes partial knowledge, ego, and misplaced confidence are more dangerous than no knowledge of a subject. With electronic design, misinterpretations and misunderstandings can lead to circuits that fail to function as expected. To an inexperienced designer, some circuits look like they should work. Meanwhile, the experienced engineer cringes, wondering how someone can get themselves in such a fix. This application note presents three case studies that illustrate how some simple analysis and a proper understanding of the laws of physics can educate designers to avoid similar issues in future designs.

Get smart - Embedded Analytics Technology

2013-05-22T13:14:46-07:00

When a driver starts a car, he doesn’t think about starting an intelligent analytics system; sometimes, that’s precisely what he’s doing. In the future, we will encounter intelligent systems more often as embedded analytics is added to applications such as automotive vision, security and surveillance systems, industrial and factory automation, and a host of other consumer applications. Texas Instruments Incorporated (TI) has been innovating in embedded analytics for more than 20 years, blending real-world, sensor driving technologies like video and audio with embedded processors and analytics algorithms. TI provides software libraries and development tools to make these intelligent applications fast and easy to develop. Now, high-performance, programmable and low-power digital signal processors (DSPs) are providing the foundation for a new wave of embedded analytics systems capable of gathering data on their own, processing it in real time, reaching conclusions and taking actions.

360 Deg Angle Position Sensing IC

2013-05-22T12:05:59-07:00

The AKM EM-3242 Non-Contact Angle Position Sensing IC is a very small, low cost and easy to use angle position sensor with a continuous 360 degree range. The EM- 3242 provides an absolute position output which means the power can be removed then reapplied and the output will continue to have the correct angle even if the rotating magnet moved while the power was off. The device requires very little power and operates at 3V+/-10%. The EM-3242 senses the angle of magnetic ﬁ eld component that is parallel to the plane of the device package and provides an analog output voltage of 10% to 90% of the supply voltage for a mechanical angle range of 360 degrees of rotation. The device includes a power down ( PDN ) function which reduces the current draw to less than 10uA.

Next-Generation Rain Light Sensing

2013-05-22T08:43:07-07:00

Automatic wipers have become virtually ubiquitous in high-end vehicles, but how can manufacturers circumvent the challenge of false wipes? Sam Maddalena, Melexis’ Optoelectronics Business Unit Manager, explains.

Diesel Engine ECU Systems

2013-05-21T15:45:37-07:00

Among internal combustion engines, diesel engines boast excellent thermal efficiency and can burn fuel that is not highly refined. They use a compression ignition system in which intake air is pressurized and fuel is injected into it, causing it to self-ignite. Such systems are not prone to knocking even when supercharging is used, so most diesel engines are used in conjunction with superchargers.

Optical-based Analog Front End for Low -Speed Powerline Communications

2013-05-20T09:19:06-07:00

The use of high-voltage power lines to carry voice signals has a history dating back to the early 1920s, with lowfrequency amplitude-modulation systems operating over lines with voltages as high as 220,000—providing reliable voice links between power generating stations and dispatchers’ offices. Later, the power utilities’ carriercurrent communications systems were refined to use single-sideband (SSB) multiple-carrier technology, and gradually expanded to include telemetry. This provides continual monitoring of load, voltage, and other powersystem characteristics, as well as remote control of switching stations in remote locations.

RD: A High-Current Power Supply with Lossless Current Sensing

2013-05-20T05:03:29-07:00

Abstract: This reference design shows how to use a MAX5060 current-mode, step-down power-supply controller to implement lossless current sensing for high-current applications. In this design, the series resistance (DCR) of the inductor is used for current sensing to avoid power loss in the current-sense resistor.

Automotive CMOS Image Sensors

2013-05-19T18:42:50-07:00

After penetrating over a decade the consumer and industrial world, digital imaging is slowly but inevitably gaining marketshare in the automotive world. Cameras will become a key sensor in increasing car safety, driving assistance and driving comfort. The image sensors for automotive will be dominated by CMOS sensors as the requirements are different from the consumer market or the industrial or medical markets. Dynamic range, temperature range, cost, speed and many others are key parameters that need to be optimized. For this reason, automotive sensors differ from the other market’s sensors and need to use different design and processing techniques in order to achieve the automotive specifications. This paper will show how Melexis has developed two CMOS imagers to target the automotive safety market and automotive CMOS imagers in general.

Measurement of Load Impedance for PA Matching

2013-05-19T16:08:34-07:00

The AJAV-5xxx family of power amplifiers (PAs) are complete, high-performance power amplifiers for GSM/UMTS mobile handsets, data cards and modems. Based on a unique, patented architecture, the AJAV-5xxx integrates circuitry for power regulation, PA bias, input and output matching, and power control. The PA enables a single connection to the battery and is implemented in a standard CMOS process.

Capacitor Charge/Discharge Circuits

2013-05-19T13:48:29-07:00

There are many applications which require pulse power. The needed burst of energy is derived by rapidly discharging a previously charged capacitor. As the energy stored in a capacitor is equal to 1/2CV2, higher voltage gives considerably greater pulse power.

GUI MIddleware

2013-05-18T14:58:07-07:00

User interfaces on many products such as mobile phones, MP3 players, portable games, and industrial and in-home control monitors are becoming ever more visually and graphically interactive. Graphical User Interfaces (GUI) incorporate highly developed visual control features using a touch panel LCD screen, which provide the user with an attractive and easy method to control the product.

Designing RC Snubbers

2013-05-18T14:20:35-07:00

This document describes the design of a simple “RC snubber circuit”. The snubber is used to suppress high-frequency oscillations associated with reverse recovery effects in power semiconductor applications

Selecting an Appropriate ESD Device

2013-05-18T13:00:25-07:00

Board designers today are confronted with a multitude of choices for ESD protection. Often the designer is constrained by certain limits such as the amount of parasitic capacitance his/her application can withstand or the required ESD level the board must pass without fail. More often than not, the constraints do not narrow down the available number of ESD devices to a manageable list. This white paper will provide guidance to the designer that will help him/her in choosing an ESD device that will give the best chance of a successful first pass design.

Switching IC for Off-Line Power

2013-05-18T12:00:54-07:00

LinkSwitch-II is a highly integrated monolithic switching IC family designed for off-line power supplies with outputs up to 6.1 W. Ideally suited for chargers, adapters, auxillary supplies and LED drivers, LinkSwitch-II provides constant voltage and constant current (CV/CC) output regulation without using an optocoupler or secondary feedback circuitry. The integrated output cable voltage drop compensation (LNK61x only), transformer inductance compensation, and external component temperature variation compensation allow high accuracy even at the end of the output cable. ON/OFF control optimizes efﬁ ciency across load and line, enabling designs to easily meet no-load and power supply efﬁ ciency requirements.

100W Power Module

2013-05-18T11:00:25-07:00

See the amazing thermal performance of Intersil’s new ISL8225M, the industry’s best thermally performing single 30A/dual 15A power module. This simple to design in module can deliver up to 100W of power from a tiny 17mm sq. QFN package.

USB Battery Charging: A Survival Guide

2013-05-17T15:46:27-07:00

The Basics of USB Battery Charging: A Survival Guide

Abstract: Arguably the most useful part of USB’s power capabilities is the ability to charge batteries in portable devices, but there is more to battery charging than picking a power source, USB or otherwise. This is particularly true for Li+ batteries, where improper charging can not only shorten battery life, but also can be a safety…

Placeshifting Video to View it Anytime, Anywhere

2013-05-17T09:49:51-07:00

Video is everywhere, available to users of handheld devices with Internet broadband access virtually any time, any place, and in many formats. One of the major consumer electronics industry challenges in recent years has been to conveniently, seamlessly, and consistently deliver video across a broad range of formats.

First Look at the BeagleBone Black

2013-05-16T12:26:38-07:00

Introducing the BeagleBone Black, beagleboard.org’s NEW high-power and low-cost development platform! Learn more at http://www.mouser.com/beagleboneblack

How FRAM RFID Improves the Medical Sterilization Process

2013-05-16T10:00:47-07:00

Medical devices and supplies need to be carefully tracked throughout their entire product lifecycles: from manufacture (including sterilization) to storage, use and disposal. Fortunately, Fujitsu’s ferroelectric RAM (FRAM), combined with RFID technologies, simplifies the task of assuring that these vital products are safe. Critically, the inherent radiation tolerance of FRAM makes it ideally suited for medical applications where gamma radiation sterilization is commonly used.

Solutions for Wireless Sensor Networks—Part 2

2013-05-16T08:45:23-07:00

Exciting global market opportunities are opening quickly for new electronic products that can serve and enable the emerging smart society. Renesas Electronics Corporation is continuing to invent and develop advanced semiconductor solutions for this area, especially devices for implementing wireless sensor networks, the subject of our two-part EDGE series. This second story examines Body Area Networks, explains electric-field communication and highlights some promising BAN applications.

Pop and Click Artifacts in PC Audio Systems

2013-05-16T05:00:58-07:00

Pops and clicks are audible, undesirable noise artifacts that occur when an unintended analog signal is passed through to an audio output device (i.e., headphones, speakers, and so on). These unintended analog signals are typically produced when an audio input or output undergoes a state change, for example, during jack retasking or device power state (D3, D2, D1, D0) changes. These state changes often result in an instantaneous DC voltage shift on the input or output signal path. The DC voltage shift, if large enough in magnitude, will result in an audible artifact during playback or record events.

DSP Technology for Flexible Femtocell Design

2013-05-15T13:11:40-07:00

Enterprises are increasingly exchanging wired connections for mobile phones, and smart phones are quickly becoming a primary means of Internet access. Together, these changes are accelerating the evolution toward wireless video and audio and creating an unprecedented increase in the volume and nature of wireless network traffic. The high data rates and bandwidths required to support these applications are a challenge for supporting today’s networks.

Enhance ADC Dynamic Range

2013-05-15T12:06:16-07:00

The AK5388 high-performance four-channel 120dB ADC may be designed into systems achieving even higher dynamic range by employing “Mono” mode system design techniques. This “Mono” mode in principle is digitally summing the ADC channels containing the same desired analog signal while digitally attenuating the output, such that the desired signal correlated between individual channels is maintained while the uncorrelated noise due to conversion is effectively decreased by 3dB. If two channels are combined into one, the dynamic range increases theoretically by 3dB. In this manner, the AK5388’s four channels may be combined into two channels at 123dB theoretical dynamic range. If even higher performance is desired this technique may be cascaded, essentially combining four channels into one digital output at 126dB theoretical performance.

Making LED Lamps Compatible with Electronic Transformers

2013-05-15T10:02:32-07:00

Abstract: There are differences between the operation of low-frequency AC transformers and electronic transformers that supply current to MR16 lamps, and there are also differences in the current draw for MR16 halogen lamps and MR16 LED lamps. These contrasts typically prevent an MR16 LED lamp from operating with most electronic transformers. This article explains how a high-brightness (HB) LED driver optimized for MR16 lamps will allow LED lamps to be compatible with most electronic transformers.