Signal Integrity

What is Signal integrity?

This is one of the emerging fields in the electronic industry. As quoted by Dr.Howard Johnson "Signal integrity is a field of study half way between digital design and analog circuit theory."

Signal Integrity is an engineering pratice

-that ensures all signals transmitted are recieved correctly,

-that ensures signals don't intefere with another in a way to degrade the reception,

-that ensures signal doesnot damage any device,

-that ensures signal don't pollute the electrmoagnetic spectrum.

what actual it means, at low frequencies, an ordinary wire will effectively short the two circuits. this is not the case at high frequencies. At high frequencies, only a wide flat object can short the two circuits. The same wire which is so effective at low frequencies has too much inductance to function as a short at high-frequencies. we might use it as a high frequency inductor but not as a high frequency short circuit.

Is this common occurence? Do circuit elements that work in one frequency range normally not work in different frequency range? Are electrical parameters are that much frequency sensitive?

Yes.

Due to the high speed, boards are experiencing the problems.

The Four High speed SI Problems:

1. Signal Quality

2. Cross Talk

3. Rail Collapse

4. EMI

For deeper discussion on SI problems, please wait for the next article

For the Deeper understanding about high speed digital design and circuits please refer the below references.

References:

1. High Speed Digital Design By Dr.Howard Johnson, Martin Graham.

2. Signal Integrity - Simplified By Eric Bogatin

3. High Speed Digital System Design - A handbook of interconnect Theory and Design Practices By Stephen H.Hall