how to calculate total power consumption

[vinodv]

How to calculate total power consumption of a circuit using Cadence virtuoso? pls help, thanks in advance

 

[Baas Rietrot]

Measure the current used at the power supply. P=VI
When you are using gates then there might be a bit more calculations needed.

 

[vinodv]

Thanks, I have one more doubt. From that total power , how to find dynamic power,static power and leakage power ? Then is there any relation between the leakage power and static power?
For this calculation is it required to go for RC extraction?

 

[Baas Rietrot]

I am sure you can find this somewhere, library/internet etc. This is a good digital CMOS book: CMOS Digital Integrated Circuits Analysis & Design by Sung-Mo Kang & Yusuf Leblebici from McGraw-Hill with ISBN:978-0072460537

The average dynamic consumption (From the above book):

\[P_{avg} = C_{load}V_{DD}^{2}f_{CLK}\]

There is also the short circuit current to be considered.

\[P_{avg,sc} = \frac{1}{12}.kf_{CLK}\tau.(V_{DD}-2V_{T})^3\]

For a symmetric inverter

\[\tau = \tau_{rise} = \tau_{fall}\]

\[k = k_{n} = k_{p}\]

There is also your leakage power dissipation.

The total power consumption will be the dynamic, static, leakage and short circuit added together.
This will give you a rough idea of the power consumption, consumption might change in pipeline and
other typologies.

 

[vinodv]

Hai Bass Reitrot,

thanks for ur help. but for calculating Pavg I should know the Cload, for that I should go for RC extraction in Virtuoso? I hope........then other power consumptions like static , leakage, and short circuit.... I should know Istatic, I leakage, Isc......... for that computation any direct method in cadence virtuaso... I am new to cadence.....

 

[Baas Rietrot]

I am unsure of any direct methods. Usually you calculate the components/currents/capacitors by
hand which is already an estimate and then you measure afterwards in Virtuoso.