Overshoot and Ringing

[doofus32]

Today, in high speed IC, the rising time for the output is often shorter than 1 ns.

This cause ringing on the line. This ringing will cause the voltage to go over the voltage that are sendt out. In the teori the double voltage.

Will this double voltage have the possibility to damage the input/output of the IC/Other IC on the board.

 

[hr_rezaee]

hi
I think it can't damage other IC.
but, it can damage information.
regards

 

[cyberblak]

Hi,

These disturbances generally aren't destructive. Of course they still should be minimized...

 

[dyfly]

Now every IC have protection circuit for it's input circuit. so it seems ok. But the data info maybe be destroyed.

 

[we_n_joy]

The ringing is because of the reflected signal, so its always better to have the proper termination to have the reduce the reflections.

 

[Shohdy]

Hi,
In a moderate design, the voltage will never go to double the intended voltage.
So there is no damage. Ringing and peeking is usually below 50% of voltage.

Regards,
Shohdy

 

[agump]

If ringing is too high , it will introduce high crosstalk. So , ringing should be avoided if possible

 

[SFactor]

the problem of ringinig is due to the mismatch in the signal integrity, try to has some termination resistor to eleimintae them as i think they can damage the data. your data will be corrupted

 

[Nimer]

hi
this depends on the duration of ringing pulses ..


regards

 

[kelvinyuan]

Hi,

This causes EMI issue also!

 

[aland]

This idea is used commonly with PCI cards and is known as reflected wave signaling. To get a 3.3V signal a 1.8v signal is sent and a short time later the reflected wave will show up at 3.3 ~ 3.6V, *because the data line is unterminated*.

To avoid ringing use termination resistors, it increases power disipation and signal rise times (dv/dt), but restricts overshoot.

However many IC's (especialy CMOS) have an input protection network of diodes and resistance that protects the input from overvoltage low current spikes. Look at the datasheets for the particular device