Articles by Steve Sandler

Benjamin Dannan and Steve Sandler teamed up to explore the tradeoffs for various calibration methods and offer some recommendations and considerations to make accurate sub-milliohm impedance measurements.

This article explains the steps to use a TDR to measure very small values of inductance and capacitance, including tips for better measurements.

It pains me to say this, but there is such a thing as turning the TDR up too high and it is also easy not to have enough. If there is a “too high,” and a “not high enough,” there must also be a “just‐right,” or Goldilocks, setting. Using measurements, and a smattering of math, the Goldilocks setting answers
will be clear. Read on to find out how.

Check out this description of what is likely the fastest GaN edge-speed ever recorded.

Many designs today include three different value decoupling capacitors, or when using just one capacitor, a small value like 0.1 uF. These recommendations are based on 50-year-old assumptions that do not apply today. It is time to reconsider these out of date, legacy design guidelines.

Poor control loop stability results in degraded power supply rejection ratio, transient response, output noise, and, for mixed signal circuits, degraded jitter. Datasheet application examples and reference designs do not often include stability information, and measurements often conclude the stability is poor.

We searched for a superior cable for PDN measurements, then decided to create our own. Here’s the story.

The voltage regulator module (VRM) contributes system level noise in several ways. Power integrity (PI) engineers tend to focus on transient voltage noise related to high-speed dynamic current. Many PI simulators ignore the VRM noise and use an ideal resistor and inductor model to represent the VRM. This overly simplistic approach misses many potential system level issues.

Obtaining accurate measurement data requires either accurate knowledge and accounting for the probe and fixture influence OR calibration methodology to remove these effects prior to measurement.

When you make a 2-port shunt through measurement using a commercial vector network analyzer the measurement includes an undesirable ground loop. Left uncorrected, the ground loop introduces significant errors. This paper shows how to solve this problem.