Effectiveness of the Ground Plane

Many vendors have come up with interdigited capacitors (or IDCs). These extra low ESL capacitors are based on the same principle with which I built my monolithic 5V/50A Flyback described in Chapter 5, titled Maximizing the Effectiveness of the Ground Plane. See Figure 4-17. As you can see, they must have been a pain to lay out inside the chip, but wait until you try to connect them on your PCB without defeating the very purpose they... 

In the circuit of Fig. 1, the ratio of the branch currents is fixed because of the permanent hole in the shield. The inductance switch, however, is a device that provides control over a hole in the shield plane. In other words, the switch can establish a virtual hole in the diamagnetic barrier, and remove it again. This is accomplished by destroying the superconductivity of a section of the ground plane, thereby eliminating the Meissner effect in that section. Circuit conductors passing over this artificial hole thus have extremely high relative inductance in that area. 

The effect of a ground plane was also well understood, but no particular interest was ever visible in the technical community. In fact, when the author mentioned the concept to a group of engineers, he was politely laughed out of the room with comments like We do not need an overpopulated array Which of course would drive the price tag up. And nothing can make tears run down faster over the fat cheeks of managers than a frontal attack on their billfold. 

You have to follow the gray current loops that show how the Gate drive current flows. The lower Fet is in effect very close to the IC, because the ground plane cancels most of the... 

Dielectric constant is directly proportional to the capacitance of a material. Present computer operations are limited by the coupling capacitance between circuit paths and integrated circuits on multilayer boards since the computing speed between integrated circuits is reduced by this capacitance and the power required to operate is increased.11 If the dielectric constant is reduced a thinner dielectric provides equivalent capacitance, and the ground plane can be moved closer to the line, so that additional lines can be accommodated for the same cross-talk. Thus, the effect of a low dielectric constant will be to increase the speed ofthe signal and improve the density of the packaging, and this will result in improved system performance.2... 

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