Performance Increasingly Tied To I/O

Speeding up input and output is becoming a cornerstone for improving performance and lowering power in SoCs and ASICs, particularly as scaling processors and adding more cores produce diminishing returns. While processors of all types continue to improve, the rate of improvement is slowing at each new node. Obtaining the expected 30% to 50% boost in performance and lower power no longer can ... » read more

Lessons Learned In 4G LTE

By Ann Steffora Mutschler While 4G LTE has moved into the mainstream, there are lessons to be learned about these very complex modems, especially from the perspective of balancing power and performance. The road to mainstream wasn’t exactly smooth sailing. “4G LTE initially got a bad rap for battery life, for power consumption,” said Pete Hardee, low-power design solution marketin... » read more

iPhone 5 – Verizon has a hit!

By Cary Chin My iPhone 5 was delivered to my door as promised on Sept. 21. The UPS guy had a truck full of them, and seemed quite happy to be getting so much attention as he was making his rounds. As with every other iPhone, I carefully unboxed it with some anticipation, but somehow I felt like there was less excitement this time around. After 5 years of iPhone mania, was the luster starti... » read more

4G LTE Vs. 3G, Part II

By Cary Chin Last month we saw some interesting data in our investigation of energy efficiency of 4G LTE transmission versus 3G transmission on the new iPad. The data above suggests that in 4G LTE mode, the new iPad used roughly the same amount of energy (3.8Wh) for viewing our test movie (Star Trek, 2:06:46, 138MB) locally vs. streaming it from the Internet. In contrast, using the 3G r... » read more

Unexpected Results

By Cary Chin In my ongoing quest to understand power efficiency at the product level of our amazing gadgets, I’ve been trying to set up experiments to compare 4G LTE and 3G data transmission. It seems to make intuitive sense that transferring data faster (my Speed Test runs show Verizon 4G LTE speed up to 20Mbps, vs. a maximum of around 700Kbps in 3G in and around Palo Alto) should consume m... » read more

4G Power Hog?

By Cary Chin After some frustrating inconsistencies in measuring energy efficiency of the new iPad in 3G and 4G LTE modes last month, I decided to start over and take a complete set of data. Although it takes a long time, sometimes it just makes sense to start again. The data I took this month isn’t completely consistent with my past measurements, but it feels like whatever is causing the in... » read more