A set of design issues such as crosstalk, cross-coupling effect, electromigration, and IR drop is called a signal integrity issue. Signal Integrity may be affected by various reasons, for example,

Crosstalk

The crosstalk creates undesirable voltage spikes known as glitches. This may further violate setup and hold time violation. Due to the cross-coupling of the capacitor, the signal at one net/wire can interfere with the signal on the neighboring wire. This disruption of the signal is known as crosstalk. If two signals are close enough, they can cause crosstalk due to coupling capacitance

How can you avoid crosstalk?

• Shielding
• Use multiple vias
• Insertion of buffer
• Use the guard ring
• Increase the spacing

How multiple vias are used to reduce crosstalk?

As we use multiple vias, Vias are introduced, and the resistances will be in parallel, which will reduce the RC delay and further decrease the crosstalk accordingly.

How the spacing reduces the crosstalk?

When the spacing between the two conductors is more, the width is increased. The cross-coupling will be reduced and consequently, the crosstalk will be reduced.

Crosstalk delay in VLSI

When one net is switching at a faster rate and the other is switching at a slower speed, due to crosstalk, the speedy net will boost up the slower net. This is known as a crosstalk delay.

Crosstalk noise in VLSI

In this, one net is idle and the other net is in transition mode. There may be the introduction of unwanted signal transition due to the coupling capacitor. The reason for crosstalk noise is the charge storage effect, power supply, or substrate noise. The crosstalk noise analysis tool determines the worst-case glitch on the idle net. This is called crosstalk noise.