about on-chip capacitor

[phanikiran]

what is on-chip capacitor? what is the purpose and typical value of it ?

 

[moh.haroun]

on chip capacitors are capacitors placed inside the chip or integrated circuit. Usually they are placed between pins and ground for filtering purposes or between dc pins and ground for decoupling.

 

[erikl]

... what is the purpose and typical value of it ?

Additionally they are used for coupling and decoupling of ac signals, and for switched-capacitor (SC) circuits (to hold and transfer charges).

Values range from about a few tens of fF, mostly 0.1pF to a few pF, but I've also seen such in the order of 10pF (seldom) and even more (very rarely).

 

[crutschow]

They are also used in op amps for frequency compensation.
The only 741 was the first op amp with internal compensation, and it used an on-chip capacitor of 30pF.
It was physically quite large and dominated the chip area.

 

[leo_o2]

The on-chip capacitor can be used for on-chip oscillator.