Well if the supply voltage is DC, then frequency is below the range of interest, 9kHz->daylight?. if the interest is in the AC, or RF if you will, in the frequency range of interest, then if the peak is below the limits, you are home easy, and I don't know of a relationship between RMS and QP - that would be an interesting academic exercise. So, given that you have some level of peak, RMS, QP, AC above 9 kHz energy riding on top of the DC supply, then depending on the "antenna" or radiating structure, this could be a hugh problem, or none at all, generally speaking. jun feng <junfeng.zhou@xxxxxxxxx> wrote: Hi, Generally speaking , what is the relationship between the digital circuits radiated emission( peak emission or maybe RMS ?) and the supply voltage ? I could not find an exact answer for this. Maybe you guys here can educate me ! Thanks, regards, Junfeng ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: http://www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: http://www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu --------------------------------- Get your own web address. Have a HUGE year through Yahoo! Small Business. ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: http://www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: http://www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu