Analog Hotspot

Based on the amount of e-mail I received after Part 3 of this series (Nov. 7, 2008, p. 18; www.electronicdesign.com, ED Online 19948), many of you have already guessed that an incremental integrator is really just a delta-sigma modulator (DSM). Well, you’re right! It actually is a continuous-time delta-sigma modulator....

Maxim Integrated Products has teamed up with Varioptic to pioneer a complete package for digital still and video camera and cell-phone makers that want to replace powerhungry, noisy hard lenses with liquid lenses. The problem with hard lenses? Focusing them involves physically moving the lens elements with motors— most recently voice-coil affairs that drain batteries and tend to leave distracting noises on video soundtracks. What’s a liquid...

Microelectromechanical systems (MEMS) and other technologies may represent a paradigm shift as analog chip makers struggle with immediate and long-term challenges (see “Analog Survival Means Learning To Be Adaptable,” p. 17). This is the way Todd Borkowski, marketing manager of the Micromachined Products Division at Analog Devices, characterizes the thinking behind the development of ADI’s MEMS technology, relative to the limitations of electret condenser...

A dapt! That’s always a good notion in a period of change. It becomes a matter of customer relations, long-term vision, product pull from deep in the future, and the ability to draw a roadmap from here to there. For example, traditional suppliers of silicon-based analog products are adapting their product lines to microelectromechanical systems (MEMS). Analog Devices and Wolfson Microelectronics surprised me last fall with briefing requests related to...

It’s curious how a nascent trend can unleash a breakthrough technology with far-reaching effects. The case at hand involves an evolving movement toward the commoditization of basestations that tends to favor direct-conversion receivers, according to Nitin Sharma, product marketing manager for high-speed converters at Analog Devices. This trend led ADI to look at the continuous-time (CT) sigma-delta architecture for a standalone analog-to-digital...

When I report on new products, I usually avoid claims that chips are “so many percent” better in some way than their competitors. That’s because specsmanship is a constant game of leapfrog. Sometimes a focus on specs can lead to an awkward situation. For example, Texas Instruments and National Semiconductor demonstrated the perils of dueling specifications last January by announcing new analog-todigital converters (ADCs) for the same application...

The other day, a guy wrote in requesting help. “How can I make an amplifier with adjustable positive and negative slew rates?” he asked. I instantly replied, “Easily,” and I drew this up. As soon as I got to work, I scanned and sent him the basic circuit (Fig. 1). You turn the P1 pot until the available current through R1 is adequate to give the desired maximum negative slew rate. Likewise, turn...

Representing this year’s best in the industrial category are an eight-channel, digital-input serializer from Texas Instruments and a six-degree-of-freedom (DoF) inertial sensor from Analog Devices. Both devices bring advanced functionality to industrial designs while saving significant space compared to similar solutions on the market. EIGHT-CHANNEL CONVERSION Designing high-density industrial automation systems that fit in...

When Analog Devices introduced its ADIS16209 dual-axis MEMS inclinometer and accelerometer as part of its iMEMS family late last year for industrial applications (â??Tiny Dual-Axis MEMS Inclinometer Simplifies Industrial Measurements,â?? Nov. 15, 2007, p. 34; ED Online 17442), it became an instant hit. In fact, our readers called it the Best Leapfrog of the year....

What’s a multiservice router/ switch? Multiservice routers and switches are network devices that support multiple switching and routing protocols, typically adding Multiprotocol Label Switching (MPLS) and Asynchronous Transfer Mode (ATM) switching to basic Internet protocol (IP) routing services (see the figure). From an IT-services (information ...

BOB, I’ve once again bumped into the limit of an op amp. A single op amp can provide gain or level shifting but not both at once. (I tend to disagree. A single op amp can do a lot of things. It can pat its tummy and rub its head and hop up and down on one foot and provide gain and offset. /rap) I’m feeling around for a way to do a circuit. Depending on what is happening at the time, one end or the other of the resistor may...

For portable applications as diverse as medical imaging units, professional video cameras, batterypowered software-defined radios, and industrial test and measurement designs, the 14-bit, 125-Msample/s LTC2261 analogto- digital converter (ADC) from Linear Technology dissipates 127 mW—less than one-third the power of alternative chips. The company acknowledges that much of the power savings arises from running the LTC2261 at 1.8 V (...

The data networking and telecom markets are driving the bleeding edge of bit rates for high-speed digital interfaces. However, digital-signal-processing systems in the medical imaging, wireless infrastructure, industrial, and defense industries are experiencing an I/O gap between the volume of data sourced by their data-acquisition analog front ends (AFEs) and the capability of digital-signalprocessing elements to sink the data. In most cases, data-acquisition...

A careful evaluation of process technology options is imperative to meet the insatiable demand for speed, features, and lower cost in data transmission and telecommunications ICs. High switching speeds, low noise and power consumption, and dense passive devices are critical needs for high-speed ICs used for physical-layer (PHY) applications. These include laser drivers and phase-locked loops (PLLs) for the transmitter and transimpedance amplifiers (TIAs) and...

The physical layer (PHY) of the Open Systems Interconnect (OSI) model conveys the bit stream—electrical impulse, light, or radio signal—through a network. In the context of the OSI model, the PHY embraces the physical as well as the signaling aspects of the interconnect. Here, we will focus just on the electrical issues. These days, designers are usually most concerned with serial signaling. This came about as data volumes increased and parallel buses just...

Part 2 of this series showed how a dual-slope integrator could fix the major limitations of a single slope converter, and I received several e-mails in response (August 28, p. 18, ED Online 19512). For example, Harry Bissel of WTC questioned my choice of polyester capacitors for low dielectric absorption. “I don’t believe that ‘Polyeste’ belongs in your list of...

People keep asking me when they will get to see my latest Dead Car List, where I keep track of all the disabled and abandoned cars I see on the road. Alas, while I have a couple of grocery bags of raw data on dead cars, I have not been able to find time or priority to organize them into a list. I’ve been too busy for 15 years, writing columns and other technical stuff. Here’s the real problem. Cars now just about all look the same. It used to be that I could...

BOB, You said, “I don’t recall if I’ve ever seen this circuit in print” (“What’s All This PNP Stuff, Anyhow?” Sept. 11, 2008, p. 80; www.electronicdesign.com, ED Online 19605), regarding Figure 2. See: 1. P.J. Baxandall, E.W. Swallow, “Constant Current Source With Unusually High Internal Resistance And Good Temperature ...

keep hearing people say that the cost of energy is forcing them to choose between paying for gas to get to work, or buying food, or heating the house, or paying the mortgage... So they scrimp as much as they can and then lose their house to foreclosure. That’s very unfortunate. I can’t tell you how to save money on groceries, but other people will tell you how to do that. I can’t tell you all the ways to burn less gas in your car, but it is possible...

An emerging business philosophy in semiconductor design says that the way to prosper in the new global marketplace is to use your engineering skills to design your customers’ products for them—or at least the “hard parts.” One corollary of this is that you have to keep beating your own previous personal-best benchmarks over and over again at the same old 18-month cycles, not just at some component level, but at the subsystem level. The reward is that...