How do we model decoupling capacitor

[tomhive]

Hello budddies,

How do we model decoupling capacitor with parasitics like L,C & R, where 2 putt which parasitics with De. Cap, really i don't know....

Thanks 4 hallping till now,

 

[l.sant]

The safest way is to lay it out and extract the parasitc R and C.. If the decoupling cap is large I would be concerned about the R you can get towards the supplies.. a bad (e.g. high ohmic connection) makes your decoupling worthless.. Impossible to give a rough estimation of the values, it's heavily dependant on technology !

Ciao,

LucaS.

 

[maxwellequ]

In case you are talking about MOS decoupling capacitors, check:
P. Larsson, "Parasitic Resistance in a MOS Transistor used as on-chip decoupling capacitance", IEEE JSSC, pp. 574-576, April 1997.