DITL – applying it to power analysis on smartphones

 

For those uninitiated with the DITL, here is a quick 101 on DITL: – what do you do on a typical day? That’s your Day-in-The-Life

 

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Now to relate it to our VoW blog (www.cvcblr.com/blog), here is how a DITL for verification could be nicely defined, thanks to Dave Fechser of LSI, read his excellent article on Design Specification Requirements with Verification in Mind at:http://bit.ly/J6Jswr

We at CVC follow this DITL model a lot during our training sessions especially for fresh graduates (See: http://goo.gl/aU8k2 for a PPT and download the contents from: http://www.cvcblr.com/trng_profiles/CVC_EIC_profile.pdf )

Earlier this week, Simon Segars, EVP & GM Processor and Physical IP Divisions (www.linkedin.com/pub/simon-segars/2/2a0/556) presented an excellent keynote at an invite-only, executive dinner event around the CDNLive India 2012 http://bit.ly/TxallC organized by Cadence. His theme was around the low power requirements in modern mobile devices (understandably, as the market needs this topic and who is in a better position than ARM can talk about this – being at the center of most of those smartphones!)

Simon shared some very interesting DITL (Day In The Life) of a typical smartphone with respect to its various features such as:

  • Making calls
  • Surfing Web
  • Taking pictures
  • Watching Video
  • Playing Angry Bird and other games
  • Listening to music

Now with lot of data mining and analysis

Simon showed a typical pattern that revealed 2 important data points:

  1. For a whopping 88% of the time in a day, the kind of applications that are run on a smartphone can be done using a processor with speed < 500 MHz
  2. For the remaining 12% the frequency needs to be > 500 MHz – these are the videos, gaming etc.

Agreed, your numbers may vary, but the fundamental point is – one could do lot of power saving if we have a big processor to serve the high-end apps and a LITTLE processor to attend to the regular, most-of-the-day work such as MP3 playback, phone calls etc.And this is precisely what ARM’s big.LITTLE architecture is all about – have dual cores with Cortex A-7 & Cortex A-15. Read more about it at our recent blog entry: http://www.cvcblr.com/blog/?p=585 

So whether you are doing RTL Design or Verification or analyzing performance data, try and see if this powerful DITL approach would help you – in many of our projects at CVC we use this approach extensively!

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