Re: [SI-LIST] : A Question About Power Noise.

Pat Zabinski (zabinski.patrick@mayo.edu)
Wed, 17 Mar 1999 12:58:14 -0600

Quite a few years ago, I performed a small study on capacitors
used for decoupling, and the results showed:

* given the same package style/size, use as large as
capacitance as available (i.e., decreases impedance)

* use the smallest package size that you can (i.e.,
extends usable frequency range)

Pat

On Mar 17, 9:39am, Vinu Arumugham wrote:
> Subject: Re: [SI-LIST] : A Question About Power Noise.
> Mark,
>
> Is a low value of capacitance really important? At 1GHz+, the package
inductance dominates the characteristics and so the impedance of a 0.1uF and a
100pF capacitor in an 0603 package will not be very different. As you point
out,
> for better performance at higher frequencies one would need a lower
inductance 0402.
>
> Thanks,
> Vinu
>
> Mark Randol wrote:
>
> > SMT 0603 ceramic caps are still pretty good at 1GHz+ as long as you keep
> > the value under a couple 100pF. 0402's go up through a couple GHz.
> >
> > --
> > ---------------------------------------------------------------
> > Mark Randol, RF Systems Engineer | Motorola SPS, Inc.
> > (602)413-8052 Voice | M/S EL379
> > (602)413-4150 FAX | 2100 E. Elliot Road
> > ryvw50@email.sps.mot.com | Tempe, AZ 85284
> > ---------------------------------------------------------------
> >
> > **** To unsubscribe from si-list: send e-mail to
majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE si-list,
for more help, put HELP. si-list archives are accessible at
http://www.qsl.net/wb6tpu/si-list ****
>
>
>
>
> **** To unsubscribe from si-list: send e-mail to majordomo@silab.eng.sun.com.
In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP.
si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****
>
>-- End of excerpt from Vinu Arumugham

**** To unsubscribe from si-list: send e-mail to majordomo@silab.eng.sun.com. In the BODY of message put: UNSUBSCRIBE si-list, for more help, put HELP. si-list archives are accessible at http://www.qsl.net/wb6tpu/si-list ****