A new architecture is blurring the distinction between successive approximation register (SAR) and ΔΣ ADCs, creating devices that couple high resolution with high throughput, achieving exceptional measurement accuracy and ease of integration.

A general-purpose data acquisition (DA) system has to deal with input signals ranging from millivolts to tens of volts, wide frequency ranges, and a great variety of sensor types. Getting the most out of your analog front-end involves choosing your ADC and amplifier carefully.

This column usually focuses on prosaic and proven applications for circuits and sensors. This month, though, I am going to talk about an emerging field called evolvable hardware, which potentially has tremendous applicability to designing robust sensing and control systems.

With the recent introduction of cheap ?? analog-to-digital converters (ADCs) offering resolutions of 24 bits or more, you'd think that the digital revolution is complete, and that the need for analog design has passed. Twenty-four bits gives you a resolution of better than 1 ?V on a 10 V span, so these high-resolution converters will make it easy to solve many interfacing problems with a minimum of additional circuitry.

Modern industrial automation applications—such as PLCs, factory process control, and intelligent transmitters—all demand high-performance, low-power components. Current-mode data transmission is no exception. Intelligent 4–20 mA current-mode data transmission is the preferred technique in many industrial automation applications and is a well-established standard for communications between the host computer and smart/intelligent transmitters in harsh factory environments. This article describes intelligent transmitters and explains their need for high-resolution, low-power ADCs, DACs, and isolation devices.

You can change manufacturing setups without reprogramming the sensor, which is essential for highmix, low-volume manufacturing with frequent color changes.

An adaptive antenna array system being investigated by NASA, Georgia Tech, and the University of Colorado at Boulder researchers could dramatically decrease the cost of building and maintaining ground stations, and yet disseminate Earth-observing satellite data more widely and quickly. Amazingly, the proof-of-principle arrays are constructed from PVC pipe, aluminum foil, and copper wire. Sophisticated signal-processing techniques are the key.

You all remember Ohm's law and the definition of electrical resistance as the ability of a circuit to resist the flow of electrical current. Although useful, Ohm's law applies to only one circuit element and assumes it to be an ideal resistor. Real-world circuit elements are more complex and exhibit resistive, capacitive, and inductive behavior that together define its impedance.