> > Capacitance of a parallel plate capacitor (or parallel copper planes) > > is given as: > > > > C = Eo x Er x A > > ----------- > > D > > > > Where: > > C = capacitance in Farads (F) > > Eo = permittivity of free space (8.854 x 10exp-12) (F/m) > > Er = relative permittivity (typically FR-4 is 4.6 at 1 MHz) > (no units) > > A = area of the plates (or planes) (m x m) > > D = distance between plates (or planes) (m) > > > > This equation neglects fringing effects. > ------------------------------------------------------------------------------------------------------------ > > Also assume that: > > D << length (for "A" dimension) > > D << width (for "A" dimension) > > Er >> Eo > > > From "Transmission Line Design Handbook" > by Brian C. Wadell > A book all designers of RF and high speed circuits should invest in. > It includes formulas for all types of printed devices. > spiral inductors, capacitors, resistors, T junction, Y junction, > microwave bends etc. > > Raymond Smith > Sr. PCB Designer > Tellium > Oceanport, N.J. 07757 > [log in to unmask] > Hey Do you have an ISBN number for the for mentioned book??? Please? ################################################################ DesignerCouncil E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE DesignerCouncil <your full name> To unsubscribe: SIGNOFF DesignerCouncil ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################