TYPES OF POWER DISSIPATION IN LOW POWER VLSI

 As we have discussed in last blog about the Dynamic Power, in this blog we will discuss about the remaining two types that are Short-circuit Power and Static Power


  • SHORT-CIRCUIT POWER:

                 Short circuit current occurs in a CMOS gate during signal transitions when both the nMOS and pMOS networks are ON and there is direct path between VDD and GND.

                 It is also called as CROWBAR CURRENT.

                 It contributes for more than 20% of the total power dissipation.

                 As frequency increases means like the frequency of transition increases( as we know during the transition between charging and discharging the load small current is flow from both nMOS and pMOS for small amount of time) these will also increase the short circuit power dissipation.





  • STATIC POWER:
                      Static power is consumed even circuit is off  ( when the chip is quiescent).
                       
                      This is basically the leakage effects draw power from nominally OFF devices.
                      As technology scales ,static power dissipation becomes more and more important in term of leakage power


Various causes of leakage in fabricating devices :
  1. Oxide leakage.
  2. Gate induced drain leakage.
  3. Hot carrier tunneling effect.      


Link to previous Blog: https://blogonlowpowervlsidesign.blogspot.com/2021/02/introduction-to-low-power-vlsi-design.html

Link to Next Blog: https://blogonlowpowervlsidesign.blogspot.com/2021/04/optimization-techniques-for-low-power.html




   Blog BY : Shreenath Naikwade




REFERENCES: Low power VLSI Design by Npatel online Course . prof. Indranil Sengupta
International Journal of Pure and Applied Mathematics Volume 118 No. 19 2018, 2997-3009 
NECESSITIES OF LOW-POWER VLSI DESIGN STRATEGIES AND ITS INVOLVEMENT WITH NEW TECHNOLOGIES B.Hema Latha1 1Assistant Professor, Department of Electronics and Communication Engineering, Anurag Group of Intuitions, Hyderabad, Telangana, India

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