What is crosstalk glitch and how do you fix it ?

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Amit
Posts: 15
Joined: Sat May 31, 2014 8:52 pm

What is crosstalk glitch and how do you fix it ?

Post by Amit » Sun Jun 22, 2014 4:23 pm

What is crosstalk glitch and how do you fix it ?

arunvappukuttan
Posts: 2
Joined: Tue May 13, 2014 11:13 am

Re: What is crosstalk glitch and how do you fix it ?

Post by arunvappukuttan » Wed Jun 25, 2014 10:37 pm

In the lower node designs , the routing of interconnects are close to each other . This can then be considered as "two metal sheets separated by a dielectric" which effectively means there is a measurable capacitance between these nets. This is called as coupling capacitance . This coupling capacitance has mainly two effects based on whether the signal on the "victim" net is transitioning or static . If the signal is static , the coupling capacitance has the ability to change its functional value ( Noise effect ) and if the signal is transitioning , the coupling capacitance can change the transition time and hence the delay of the signal ( crosstalk effect ) . These can be fixed using the following method .
1. Break the victim net by inserting an buffer in between .
2. Provide sufficient spacing between the victim and aggressor net to reduce coupling capacitance.
3. Route the victim / aggressor net in a different metal layer to remove coupling capacitance.
4. Strengthen the signal on the victim net by using a lower VT or higher drive strength cell .
5. Weaken the strength of the aggressor net cell . ( Least preferred ) .

Amit
Posts: 15
Joined: Sat May 31, 2014 8:52 pm

Re: What is crosstalk glitch and how do you fix it ?

Post by Amit » Thu Jun 26, 2014 6:50 pm

Thanks Arun. It helped a lot :) Can you please reply to my other queries also?

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