I am searching for specific numbers that represent the trend that
power consumption is going down in most devices.  Perhaps a DRAM logic
Chip used more power 5 years ago and the consumption is working its
way down in a curve.

I am interested most in lower power devices (below 1W) but any info is
helpful.

Price listings are an excellent source of information if they contain
the price of older models and newer models (I can make assumptions
from this information).

I have never used these services before so I am only offering $50 in
hopes of a good answer, but the tip will be sufficient for a
sufficient answer.

Thank you for your time.

---

Request for Question Clarification by techtor-ga on 08 Jul 2003 10:37 PDT

Hello Maria19,
I've been searching for numbers to quantify your hypothesis, but I've
rather found the opposite - computer systems that have slighty
increased in consumption over one year (1999-2000). I'll see if there
is more I can find.

---

Clarification of Question by maria19-ga on 08 Jul 2003 11:20 PDT

Hmmm.  I was afraid of that.  Are there certain parts of systems that
need less energy?  Perhaps parts that have become more efficient over
time?

Perhaps, are there softer requirements about energy concentration in
systems and that is why they are consuming more?

Hello Maria19,

Surely, reducing power consumption is a priority in the development of
semiconductor devices. The popularity of mobile electronics such as
notebook computers, personal digital assistants (PDA’s), and cellular
telephones stimulate the market to reduce power consumption. Consumers
require features such as web browsing, streaming video, and games.
These features require more battery life; however, battery performance
has not improved materially. So, industry must keep up by reducing
power consumption.

 
--
Trends in Die Size

0.35 micron process was used in Pentium II 266..300
0.25 micron process was used in Pentium II/III 450..600
0.18 micron process is used now in most IC’s and Pentium III 500
0.13 micron process is used now in new PC CPUs and Pentium 4

Smaller die sizes usually mean lower power consumption. Though, in
Pentium processors, the trend is reversed. Since you’ve stated that
you care for sub-watt components, we’ll ignore the discrepancy caused
by the Pentiums (which require > 20W).


---
Trends in PC RAM

EDO            5.0V                             / Max Power, 4840mW
SDRAM  150mA / 3.3V / Average I/O Power, 1020mW / Max Power, 2040mW
DDR    140mA / 2.5V / Average I/O Power,  280mW / Max Power,  950mW

Of course, specific RAM chips may be different; though, these data are
here are accurate for comparison.

Data taken from Portable Design and memory data sheets
http://pd.pennnet.com/Articles/Article_Display.cfm?Section=Archives&Subsection=Display&ARTICLE_ID=78164


---
Trends in the popular Xilinx CPLD (Complex Programmable Logic Device)

Year 1999 // XC9500        // 5.0 Volts / 288 Macrocells / 192 I/Os
Year 2000 // XPLA3         // 3.3 Volts / 512 Macrocells / 260 I/Os
Year 2002 // CoolRunner-II // 1.8 Volts / 512 Macrocells / 270 I/Os

As CPLD technology progressed over time, a digital core was created
for the CoolRunner-II that allowed for a standby current as low as
14uA.

Data taken from press releases and Xilinx CPLD page
http://www.xilinx.com/prs_rls/prs_rls.htm
http://www.xilinx.com/xlnx/xil_prodcat_product.jsp?title=cpldsolutions_cpldselect_page





To find relevant pages, I performed a Google search on the following
terms:

power trends embedded
EDO average power consumption
SDRAM average power consumption
DDR average power consumption


For more information about mobile technologies I suggest,

Portable Design Magazine
http://www.portabledesign.com/


I hope that this information was helpful. If you need any further
clarification, I would be happy to give it.

	// matic-ga

You might look at the power per transistor ratio or the power per MHz
ratio.  This might explain the discrepancy found with desktop
processors.  Of course, embedded processors (I believe) don't follow
this trend.  You might look at the 8051 as compatible processors are
still made in large quantity today, while it was invented in 1980 (by
Intel).  I would expect to see a decline in power usage on these.

Bradley

I believe just a little clarification is required. Power consumption
of single semiconductor devices has gone down. However, the speed
(frequency) at which they operate has gone up, causing a higher power
consumption in some devices. This is why computer power supplies have
grown (higher wattage ratings).

If your referring to semiconductor devices in general, then it could
go either way. A lot of semiconductor operating voltages have went
down but that does not mean the power consumption has necessarily went
down. There may be data catagorizing the function of the semiconductor
with data trending the years vs. its power consumption . However, if
you just want to compare RAM (random access memory) chips then an
answer is more likely, if want to compare logic chips (AND, NOR, NAND,
OR, etc) then an answer is likely achievable.