Area and power

Hi,
   How is area of the memory that you use related to energy consumption
in an memory device. So if I have two memory devices of same capacity,
one larger than the other, can I comment on its energy behavior just
based on the area.



thanks 
Shrey

shrey wrote:

> Hi,
>    How is area of the memory that you use related to energy consumption
> in an memory device. So if I have two memory devices of same capacity,
> one larger than the other, can I comment on its energy behavior just
> based on the area.

Not really. First you can only compare die sizes
of identical technologies. And the power consumption
is at least for the SRAM proportional to number
of accesses. Meaning no access, no power. That
means except the idle power which increases with
decreasing feature size.

Rene
-- 
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

Rene Tschaggelar wrote:
> 
> shrey wrote:
> 
>>    How is area of the memory that you use related to energy
>> consumption in an memory device. So if I have two memory devices
>> of same capacity, one larger than the other, can I comment on its
>> energy behavior just based on the area.
> 
> Not really. First you can only compare die sizes
> of identical technologies. And the power consumption
> is at least for the SRAM proportional to number
> of accesses. Meaning no access, no power. That
> means except the idle power which increases with
> decreasing feature size.

But just the opposite for dynamic ram, where the refresh charge is
proportional to the size of the storage capacitor, and the refresh
rate is proportional to its leakage rate.  This is pretty well
independant of the power for actual access and use.

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But what abt its switching power ? Does that depend on feature size ?
More area, is it possible they use more capacitors ?


Shrey
Rene Tschaggelar wrote:
> shrey wrote:
>
> > Hi,
> >    How is area of the memory that you use related to energy consumption
> > in an memory device. So if I have two memory devices of same capacity,
> > one larger than the other, can I comment on its energy behavior just
> > based on the area.
>
> Not really. First you can only compare die sizes
> of identical technologies. And the power consumption
> is at least for the SRAM proportional to number
> of accesses. Meaning no access, no power. That
> means except the idle power which increases with
> decreasing feature size.
>
> Rene
> --
> Ing.Buero R.Tschaggelar - http://www.ibrtses.com
> & commercial newsgroups - http://www.talkto.net

shrey wrote:

> But what abt its switching power ? Does that depend on feature size ?
> More area, is it possible they use more capacitors ?

I think that most manufacturers of DRAM
have been using well and trench capacitor
memory cells for a number of years.  That
would make any direct comparison of 2D area
difficult or impossible.

Engineers use data sheets to determine
energy consumption, not calipers (:

Please don't top-post.

> 
> Shrey
> Rene Tschaggelar wrote:
> 
>>shrey wrote:
>>
>>
>>>Hi,
>>>   How is area of the memory that you use related to energy consumption
>>>in an memory device. So if I have two memory devices of same capacity,
>>>one larger than the other, can I comment on its energy behavior just
>>>based on the area.
>>
>>Not really. First you can only compare die sizes
>>of identical technologies. And the power consumption
>>is at least for the SRAM proportional to number
>>of accesses. Meaning no access, no power. That
>>means except the idle power which increases with
>>decreasing feature size.
>>
>>Rene
>>--
>>Ing.Buero R.Tschaggelar - http://www.ibrtses.com
>>& commercial newsgroups - http://www.talkto.net
> 
>