OPTIMIZATION TECHNIQUE FOR LOW POWER VLSI 2

                                           Supply Voltage Reduction

These is the one of the most impactfull approach towards the techniques to reduce power in Low power vlsi.


There are 2 design alternatives:

1.Static Approach 

2.Dynamic Approach.


                                                           Static Approach

 Where the distribution of power supply voltage is fixed but there is priority based supply among various functional blocks.It is done on design part of circuit

                                       By taking the reference of fig  as we know the in the static approach the voltage supply which is connected to different part of circuit depends on the functionality or the priority of circuits.

                                 Some times we need the circuit in which the speed of that circuit doesn't matter but speed and performance of other circuit matters. So here we can reduce the power consumption by reducing the power supply to that particular circuit whose performance can be slow or which requires low supply voltage.
                                 Let's take example ,in fig. there are two blocks of circuit one is slow part and other one is fast part .By  refering the theory of static approach we can say that circuit which requires lower voltage supply or  slow operation, we can connect it to low supply voltage.

                               And the circuit block which is fast which requires high supply voltage is connected to the high supply voltage.                          

 By taking above example ,there are Two supplies so as the number of supplies increases,the complexity of circuit will also increase(power routing).There are two voltage supplies one is high level voltage supply and other one is low level voltage supply depending upon priorities we can connect the supplies accordingly.


                                  As both functional blocks works on different supply voltage sometimes there is requirement of voltage level translation.



                                                         Dynamic Approach 

 In these you have an instuction (program)  to execute the performace of that operating system. The power supply voltage is changed as required.

                                      As it is not related to design part it provides flexibility and does not limit performance.

                                   
  Ex. Laptop offers us different operating mode.





BLOG BY - SHREENATH NAIKWADE



LINK OF PREVIOUS BLOG: https://blogonlowpowervlsidesign.blogspot.com/2021/04/optimization-techniques-for-low-power.html







     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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