Power Calculations for Pure Sine Waves

Figure 1: For a purely resistive load,
power = voltage * current, with both vectors in phase

Wouldn't it be wonderful if every sine wave we encountered in the real world was pure, with no distortion? It sure would make life easier. Alas, it's pretty much never the case. But in reviewing sinusoidal power calculations, it's best that we begin with the simplest case: a single, pure sinusoidal line voltage and single, pure sinusoidal line current supplying a linear load.

DDR Memory Testing Part III: What Not to Do

Figure 1: Damping resistors on
solder-in probe tips

Testing of dual data-rate memory (DDR) devices and/or modules calls for careful application of some best practices for probing. There will also be cases where the use of chip interposers is called for. Heeding the advice provided in earlier Test Happens posts on this topic will go a long way toward successful probing and testing.

The Realities of Oscilloscope Probes

Figure 1: Teledyne LeCroy's ZS2500

high-impedance active probe

Looking for a good, albeit very expensive, paperweight? Try using an oscilloscope without probes! Probes are often taken for granted but they are one of the most critical elements of the signal chain in any test scenario.