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For this project, we will use an Atmel 328 microcontroller demo board, prepared with firmware to control it explicitly for our purposes, and with coaxial cables connected between the I/O pins and the input to the active probes of the scope. This interconnect provides a high bandwidth transmission line path for the signals.

If the die's I/O power rails are shared by the core power rails, here's a way to get your core power-rail measurements anyway.

How do you achieve high bandwidth in your measurements while minimizing current load on your DUT? Given that your DUT is a power rail, you really don't want to draw too much current from it., or your measurement system will distort the rail. But these two measurement criteria are at loggerheads with each other. It's a quandary, and it has to do with the fundamental nature of signals on interconnects.

Measuring the noise on a power rail seems to be a straightforward task. However, there are some basic pitfalls that can cause incorrect, or even downright strange, results. Let's look at one of these challenges: RF pickup. We'll demonstrate the effect of RF pickup on a power-rail measurement, and then we'll show you an effective means of mitigating that effect.

Eric Bogatin explains the figures of merit in the time and frequency domain, and he steps through how to get a rough measure of the highest frequency components in a signal.

Teledyne LeCroy today announced the WavePro HD high-definition oscilloscopes, which combine for the first time HD4096 12-bit technology and 8 GHz bandwidth for low noise and signal fidelity. With a maximum of 5 Gpoints of fast acquisition memory, WavePro HD oscilloscopes are designed to acquire extremely fine waveform details over long periods of time. A deep, powerful toolset quickly exposes underlying system behaviors. 

Receiver sensitivity and noise coupling to antenna are two major concerns when developing mobile devices such as smart phones and tablets. There are various causes of degradation of receiver sensitivity. However, most of the time they are due to the noise generated by digital signal harmonics on printed circuit board (PCB) patterns, which couple to the antennas. This article presents a methodology to predict noise to antenna coupling and antenna desense.

Eric Bogatin will lead this special session again at EDI CON USA, taking on the topic of how to deliver more than 100A with less than 10 mV of noise to digital devices. See how you can get involved.

Power conversion circuits with control loop(s) are everywhere in electronic systems. We must establish stability and performance metrics for control loops and their circuits. However, generally accepted metrics may not be good enough. Is a crossover frequency with 45 degrees of phase margin and 10 dB of gain margin enough? How can we relate phase margin to peaking in the impedance profile and transient noise requirements? This article aims to answer these and other questions.

VRMs and VRM controllers are often selected based on size, efficiency, price, or a relationship with the manufacturer. This often leads to a poor VRM selection, requiring additional engineering resources, greater time to market, as well as, higher BOM costs to correct the deficiencies. In this article, we evaluate the choices, define some useful figures of merit, and provide specific selection suggestions.