How to remove unwanted spike signal ?

[overmars]

spike signal

As you can see from the pic below, the spikes sometimes occur at the edge of regular logic signal and due to the considerably large spikes some system components may not work well or shut down.
How to effectively remove these unwanted spikes ?Can anyone provide me some useful materials, articles or suitable way to solve this problem?
Thank you in advance!

Regards

 

[fontp]

remove spikes signal

One possibility is median filter

https://en.wikipedia.org/wiki/Median_filter

It remove spikes without distorting edges

 

[the_risk_master]

reduce logic induced spikes

Hi,

You can also use a simple diode clipper, but it depeds on the frequency of the
rectangulare wave signal.

 

[Hero]

spike logic remove

Hi,

Another solution is to use linear low pass filter to cut high harmonics.

Possible nonlinear solution is voltage limiter based on OP AMP and diodes.

 

[Kral]

glitch differentiator

overmars,
It's usually best to eliminate the problem at its source. The most likely source of spikes is "ground bounce" or "Vcc/Vdd bounc". This is caused by:
.
1) Poor routing of Vcc/Vdd

2) Inadequate decoupling. For high speed logic families, the decoupling capacitors must have short connections between the supply and ground. Ground and Vcc/Vdd planes work well.
Regards,
Kral

 

[roykyn]

non linear median filter glitch

a simple capacitor(ceramic) ....calculated one can largely reduce it.....

 

[echo47]

filter to remove these spikes

Please clarify "regular logic signal". Is that a signal you see on circuit board full of logic? What type of logic? Is it the signal at the end of a cable? What is the time duration of that overshoot glitch? You could be seeing the results of a poor transmission line.

If it is a transmission line problem, then I suggest exploring this book:
"High-Speed Digital Design - A Handbook of Black Magic" by Howard Johnson and Martin Graham

 

[overmars]

series spike remove

Thank you all,
I'm sorry, I drew this signal on this pic as a simple example . I mean many times I can see digital signals carrying the spikes which are not clarified in the specific situation.
I want to search for general ways to solve this kind of problem.
e.g. The glitch is pretty large when going through a system which includes differentiators and integrators ,,,
Thanks ..

Regards!

 

[echo47]

how to remove spikes from signal

If you see those glitches all over a logic board, then it may have poor PC board layout, causing transmission line problems. In that case, definitely check out Johnson's book.

It is also possible that your oscilloscope probe is mis-compensated or has a too-long ground lead, causing visible overshoot glitches. However, that's only a measurement problem, it usually doesn't cause the board to malfunction.

 

[bcl]

how to remove spikes from a op amp output

Poor grounding and mismatch between the driver and the receiver can cause these overshoot problems. Sometimes a series resistor could help damping out the spikes, too.

 

[alec82]

how to remove nonlinear capacitor signal

you can use snuber network for reduce this unwanted overshoot. if u use minimum track length,u have smaller overshoot.

 

[melc]

vdd spike

Assuming is not a measuring fake problem, the spike presented in spike1.jpg could be removed by an RC or LC filter, where C could be the bus parasitic capacitance and R could be a small value (20 to 50 ohm). Better results are obtained if you'll use ferite chip beads for L. See for example here: **broken link removed**
Buses spikes can be filtered with 4 line arrays like DA1206 series from Steward.
At Digikey you may buy a sample kit K202 which contain a lots of different ferrite and arrays.