Specifications such as gain error, offset error, and differential nonlinearity help define an analog-to-digital converter’s performance. In part 1 of this series, we discussed an ideal analog-to-digital converter (ADC), noting that it would have infinite resolution and bandwidth. Then we looked at the real world of practical inverters and how their resolution, expressed in a […]
FAQ
Understanding ADC specs and architectures: part 1
Analog-to-digital converters are the heart of most test equipment, setting the stage for the digital processing of analog signals. Several posts over the past year or so have involved digital signal processing. For example, we have covered the fast Fourier transform (FFT), the inverse FFT, and discrete convolution. To perform these operations on real-world signals, […]
Phone chargers produce EMI: We compared four
The switching power supplies that regulate output voltage produce radiated emissions. Our tests compare waveforms that give clues as to how the chargers operate.
Characterize EMI from dc-dc converter ringing
Switching power supplies produce radiated and conducted emissions caused by ringing. Oscilloscope and spectrum-analyzer measurements let you see them. DC-DC converters are ubiquitous in most electronic products. While more efficient than linear regulators, they can also produce considerable amounts of interference that can affect nearby circuits. The measurements in this article show how ringing occurs […]
Review: Micsig TO3004 tablet oscilloscope
If you’re looking for a portable oscilloscope for field troubleshooting or for demonstrations, look at the Micsig TO series. Here’s my take on the four-channel 300 MHz variant, TO3004. The Micsig TO3004 oscilloscope (Figure 1) is an 8-bit, four-channel, tablet-sized portable oscilloscope that’s also available with 100 MHz and 200 MHz varieties with two or […]
How to use convolution to implement filters: part 4
A windowed sinc function can implement a low-pass filter, and a two-dimensional convolutional filter can blur or sharpen images. In part 3 of this series, we introduced a low-pass filter based on the Sinc function and described the need for windowing to compensate for sampling and truncation. Q: How can we apply this filter? A: […]
Why engineers need IC ESD and TLP data
Design Engineers need ESD and TLP characterization data to make informed decisions to design robust circuits and systems. Engineers often review semiconductor data among several manufacturers when designing a circuit or system. While two or more ICs may perform satisfactorily under normal operating conditions, they may not perform the same under extreme conditions, such as […]
How to use convolution to implement filters: part 3
A windowed sinc filter outperforms a moving-average filter in the frequency domain. In part 2 of this series, we described a type of convolution filter called the moving-average filter, and we demonstrated that it is effective at removing Gaussian white noise in the time domain but performs poorly in the frequency domain. Q: Do all […]
How to use convolution to implement filters: part 2
A moving-average filter can address white noise in the time domain but performs poorly in the frequency domain. In part 1 of this series, we defined convolution, denoted by the * symbol, and looked at a simple geometrical example of how it operates to produce a new function y(t) from two given functions, f(t) and […]
How to use convolution to implement filters: part 1
Convolution is used in a variety of signal-processing applications, including time-domain-waveform filtering. In a recent series on the inverse fast Fourier transform (FFT), we concluded with a mention of convolution and its application to filtering. Convolution Q: What is convolution? A: Convolution, denoted by * symbol, combines two functions to form a third function in […]
