Octa-core Superphones: When a Single Core is just not enough!

I was surprised to hear that the Samsung Galaxy phones will have an Octacore processor (a processor with 8 cores). A smartphone is essentially a computer – like our home computer. What do we really do on a home computer? We surf the Internet, create documents, and play movies. Among other components, a computer contains a Central Processing Unit (CPU) to perform all these tasks. Traditionally, older CPUs had a single core.

What is a ‘Core’, really? As a non-technical end-user, why do I really care as to how many cores the CPU in my smartphone has? Before answering these questions, let us talk about something else:

How does a motor vehicle with an internal combustion engine work?

Scooters have an internal combustion engine with a single cylinder, piston, and a spark plug.  When fuel is injected into the cylinder, the spark plug creates a spark and the explosion pushes the piston. Consequently, the scooter moves forward. With a single cylinder comes a limited amount of power. In comparison, the engine of a car has four cylinders. Four cylinders give more power than a single cylinder. More interestingly, the work is equally divided amongst the four cylinders. As a result, one cylinder is not overloaded and one cylinder never overheats.

Let’s compare the processor with an engine and the core with a cylinder.

The biggest challenge chip designers face today is the inefficiency of a CPU in terms of heat emission. Like single cylinder engines, CPUs with a single core produce a lot of heat which makes them inefficient in terms of power consumption. To solve this problem, chip designers created a multi-core processor (like the multi-cylinder engine). The processing is divided between multiple cores thereby reducing heat emissions and consequently reducing power consumption. It is common to see dual-core or even quad-core processors in computers today.


So far, phones usually had a CPU with a single core. With the launch of Samsung Galaxy, we are entering a new era of smartphone computing. The Samsung Galaxy S6 has an Octa-core processor (8 cores). Why does a smartphone need so much power? When a home computer can do everything with a slower processor (and single core), why does a smartphone need a faster processor (with 8 cores)?

The Samsung Galaxy has the following components that a home computer or even a basic business computer does not have:


  • GPS tracks your location.
  • Proximity Sensor turns the screen off when you hold it to your face.
  • Ambient Light Sensor automatically adjusts brightness.
  • Accelerometer senses movement and orientation.
  • Barometer measures pressure.
  • Temperature Sensor measures the temperature.
  • Humidity Sensor measures the humidity.
  • Magnetic Sensor measures the magnetic field.
  • Gesture Sensor senses your hands to navigate.
  • Infrared Sensor turns the phone into a remote control.
  • Eye Tracker pauses video when you look away.
  • NFC (Near Field Communication) shares data by touching two phones and also enables mobile payments.
  • Dual Cameras are available; one on the front and one on the back of the phone. Both cameras can record simultaneously in the Samsung Galaxy S6.
  • Dual Microphones are used in the phone; one microphone for voice and the other to listen to the ambient noise and create anti-noise using the noise-cancelling system.

These sensors constantly gather large amounts of data and need constant processing. A CPU must have multiple cores to compute all this data simultaneously. The CPU assigns tasks to different cores, keeping a single core from overheating. Less heat is generated and hence, less power is consumed.

With battery technology not evolving as fast as CPUs, manufacturers don’t have a choice but to make CPUs that are  more efficient in terms of power consumption and heat emission. Unless better batteries are developed, smartphone manufactures will strive to use better processors with each new model to remain competitive. (You might want to read more about my idea on battery technology in my earlier post Is the Smartphone Industry Curious about Curiosity?.)

Next time you use your smartphone, you might want to count the number of sensors it has. It would be really interesting to see how many of us are able to identify all the sensors on our smartphones!


Is the Smartphone Industry ‘Curious’ about Curiosity?

The world holds its breath as the next battle for dominance in the smartphone industry begins with the launch of the Samsung Galaxy S4. Apple recently defeated Samsung in a patent lawsuit involving user-interface elements. Samsung lost the battle, but they don’t necessarily have to lose the war. Samsung will not fade away into the night without putting up an aggressive fight. Samsung plans to sue Apple on its using the LTE (a technology for faster data speeds called Long-Term Evolution) chip in the iPhone 5.

As the smartphone war rages on, it is evident that there are many areas where industry giants compete for dominance – user-interface, operating system, physical design, connectivity, storage, and camera.

But there is one area where companies haven’t done much – the battery. Until the smartphone industry invests heavily into battery technology, devices are limited to what they can do on a single charge. Lithium-ion batteries are used extensively in all smartphones as of today. The life of a single charge is a few hours (assuming a user talks, texts, and uses data connections such as Wi-Fi or 3G/LTE). After a smartphone runs out of battery, users have no option but to carry a charging cable, USB charger, portable USB charger, a battery pack (like Mophie), or just wait to reach home to charge the phone.

Talking about battery life, the smartphone industry can learn a lot from the Mars Rover Curiosity. Curiosity has reached Mars and has starting sending photos, conducting experiments and, exploring the Martian mountains. For doing all this, Curiosity needs one thing – power.

Previous generations of Mars Rovers used solar panels to power various devices. However, dust settled on the solar panels making them inefficient. Also, note that the Sun looks much smaller from Mars as Mars is at a greater distance from the center of the solar system. Smaller sun = less light = less solar power.

To solve this problem of inefficient solar power, Curiosity uses a Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). Simply put, Curiosity uses the radioactive isotope Plutonium-238 as the raw material. Heat is automatically generated due to the natural decay of Plutonium-238. A device called a Thermocouple uses this heat to generate electricity. The Plutonium-238 is well shielded, and the heat – and not the radiation – is used to generate electricity. This device can last for 14 years without requiring any maintenance! Curiosity will constantly receive its power until Plutonium-238 completely decays.

Now, coming back to the smartphone industry, why can’t we design something like this for smartphones? Imagine having a very small amount of radioactive isotope that is well-shielded and attached to the smartphone. The device could then, theoretically, produce electricity for at least a year (or more!). Instead of battery packs like Mophie, we could have smartphones that generate their power and don’t need a recharge! Depending on the stability of the technology, we could have a smartphone that could last for years without a recharge. You buy a smartphone and dispose of it after a few years without charging it even once.

When I told my wife about this idea, she said, and I quote: ‘I am not carrying a nuclear bomb in my pocket!’. Well, what I am proposing is not exactly a nuclear bomb since there is no chain reaction like nuclear fission or nuclear fusion going on. The natural decay of Plutonium-238 generates heat and hence the power. Theoretically, a well-shielded pack of Plutonium-238 is safer than batteries that we have today. The current batteries have greater chances of exploding than a well-shielded pack of Plutonium-238!

The future of the smartphone industry is uncertain. There are no obvious winners as of today. In my opinion, only the company that designs and patents advanced battery technology will emerge as the winner. The company holding the key to advanced battery technology will be the undisputed winner and will rule the smartphone industry for generations to come. Simply because, more power equals to more things the smartphone can do without dying.

Hey Apple and Samsung – are you listening? Hopefully, I can expect to be paid a billion dollars for my idea!

(MMRTG Source: http://mars.jpl.nasa.gov/msl/mission/technology/technologiesofbroadbenefit/power/)

Edited by: Prarthna Sri