Hi,

How to perform DC loading analysis of a digital circuit.

Is it sufficient if we meet the Iil and Iol requirements of the receivers by the driver IC.

Regards,
Phaniendra Kundeti

 

There is not enough. It is necessary to take into account the capacity of the load, the maximum duration of the front of the input signal. With a long front, the logic element can output parasitic pulses!

 

If I understand you correctly you need to meet AC requirements
unless the logic is very low speed application, then DC would suffice.

In high speed the AC must meet not only timing but also DC logic
specs.

Regards, Dana.

 

Hi Dana,

AC requirements will be verified by taking into consideration Cin, CL , Rp and Rn values in to consideration. My question how to consider the dc requirement , will Iih, Iil values will be suffice???

Regards,
Phaniendra Kundeti

 

The DC values are the worst case switching threshold to guarantee noise margin
and logical state at inputs. Output DC values are loading, have to be met for on die
allowable rail currents, voltages into subsequent stages, Pdissapation.

Yes, it all needs to be met.

Regards, Dana.

 

thank you dana.