Wow, Percy, spoken like an EE! Rick, the other situation (that you probably will discuss in a subsequent column) is RF bypassing. The problems are similar, but the issue is more of parasitic resistance rather than inductance (minimal ESR). This gives a minimal impedance to ground near resonance. Will you be kicking this topic around? Robert Robert T. Croswell, Ph.D. Motorola Labs (847) 538-5397 (630) 400-6940 (mobile/SMS) -----Original Message----- From: EmbeddedNet [mailto:[log in to unmask]] On Behalf Of Percy Chinoy Sent: Wednesday, May 04, 2005 12:17 PM To: [log in to unmask] Subject: Re: [EM] CircuiTree Column Draft Hi Rick, The article is nicely written and easy to understand. Catchy title! When you talk about the effect on inductance from fields adding or cancelling due to currents being in same or opposite directions, you may want to specify that you are talking about magnetic fields. Also a simple formula showing relationship of inductance and capacitance with self-resonant frequency may help people understand the increase or decrease in fr. regards Percy Chinoy Global Business Manager | Rohm and Haas Electronic Materials | Circuit Board Technologies Tel: (508) 787-4697 | Mobile: (781) 363-1129 Richard Ulrich <[log in to unmask]> Sent by: EmbeddedNet <[log in to unmask]> 05/04/2005 11:50 AM Please respond to D-50 Embedded Devices Committee Forum <[log in to unmask]>; Please respond to Richard Ulrich <[log in to unmask]> To [log in to unmask] cc Subject [EM] CircuiTree Column Draft Here?s a draft of my upcoming column for CircuiTree magazine, probably to run in July. I like to show these around to my colleagues in the business to make sure they are as accurate as possible, so please look it over in the next few days and let me know if there is anything you think needs changing. Thanks, Rick ? ****************************************************** Dr. Richard Ulrich Professor Dept. of Chemical Engineering 3202 Bell Center Univ. of Arkansas Fayetteville, AR 72701 [log in to unmask] (479) 575-5645 ****************************************************** [attachment "Ulrich Column 10.pdf" deleted by Percy Chinoy/NAmerica/Shipley]