about Baker,"CMOS circuit design, layout, and simulatio

[nieco]

from second edition in this book

page 814 has a paragraph :
' in any practical regulator, a bypass capacitor is used to supply charge to the load for fast current transient...'

1. how to decide the bypass capacitor, is decided by transient speed? how to calculate this relationship ?
2 why the bypass capacitor can charge to the load ?

thx very much

 

[bastos4321]

Re: about Baker,"CMOS circuit design, layout, and simul

from second edition in this book

page 814 has a paragraph :
' in any practical regulator, a bypass capacitor is used to supply charge to the load for fast current transient...'

1. how to decide the bypass capacitor, is decided by transient speed? how to calculate this relationship ?
2 why the bypass capacitor can charge to the load ?

thx very much

1 - Check how many energy is necessary for the transient and them chose a capacitor which can supply that energy. E=1/2 C V^2
2- Since the capacitor will be placed near the load is has a lower resistance path to it than from the supply. So the fast transient will first sink current from the capacitor.

Bastos