Monday, September 17, 2012

What is Wireless Charging Technology?

Inductive charging popularly known as Wireless charging technology used in modern electronics and electric vehicles is based on the principle of mutual induction between a pair of conductors such that when there is a change in the current flow through one wire it induces a voltage across the ends of the other wire through electromagnetic induction.This is the same principle that is used in transformers.
Cell phones on an inductive charging dock.

In the case of inductive charging devices the conductors are induction coils.The charger has what's called the primary coil used to create an alternating electromagnetic field.The portable or mobile device contains the secondary coil in which the varying magnetic field induces a voltage which in turn leads to current through the coil.This induced current is used to charge the internal cell or battery of the device.
The range of the charger may be increased by using a technique called resonant inductive coupling,wherein the coils used in the charger and the charging device are identical leading to electrical resonance between the coils.This leads to greater range with a slight decrease in efficiency.
A Nissan Leaf being charged by a inductive charger.

To promote compatibility between various chargers and portable devices,the Wireless Power Consortium(WPC) established in 2008 has created the Qi (pronounced "chee") standard for mobile electronic devices.The WPC consists of more than 100 member companies representing wireless power,automobiles,semiconductors,wireless operators,etc...Popular cell phone companies include Nokia,Samsung, name a few.The Nokia Lumia 920 is one of the first phones in which this technology has been completely integrated without the need for any additional accessory.
Lumia 920 on a fatboy "pillow" charger.

 Advantages of Inductive Charging:

-Eliminates the need for cables
-Eliminates the compatibility issues     associated with various types of  connectors.
-Lowers the risk of electric shocks.
-Can be used to charge medical implants through skin.
-Can be integrated into  furniture, walls.(coffee shop table,etc..)
-Can be used with devices designed to be sealed or waterproof.

Lumia 820 with a wireless charging shell.


-Efficiency is low leading to power loss.
-Heat dissipation is more which can be harmful to certain devices.
-Device cannot be charged when its being used unless its being used on the charger.
-Charging is slower compared to traditional means.

Sunday, September 16, 2012

The (R)Evolution Of The iPhone

The first iPhone launched in 2007.
Although smartphones and touchscreens in phones existed way before the iPhone,there was a lack of products which had a perfect blend of technology,looks and ease of use(And a huge fan following...).With the launch of the iPhone in 2007 Apple changed the way the world used and perceived cell phones.It was an iconic product which changed the mobile communication industry and from then on cell phones were not just devices used to make and receive calls or send text messages,but were devices which could do a whole lot more.Lets have a look at the way the iPhone has evolved over the Years...

The Original iPhone:

Steve Jobs at the launch of the first iPhone.
The first iPhone had a plastic-metal  case and used 2G networks.It featured a 3.5 inch multi-touch capacitive touchscreen with a 320x480 pixel resolution.It was available in 3 variants 4,8 and 16GB.It had a 2MP camera and 128MB of RAM.It also featured an accelerometer,proximity sensor and ambient light sensor.It had bluetooth 2.0 and Wi-Fi.The CPU was clocked at 412 Mhz.Apple sold a million of these phones within five days of launch.It was 11.6 mm thick and weighed 135g.

The iPhone 3G:
The iPhone 3G
The iPhone 3G was launched about a year after the original iPhone in June 2008
The iPhone 3G retained the screen,camera,RAM and CPU from the Original iPhone but added features such as Assisted-GPS along with 3G data.It was available in 2 variants-8 and 16GB and runs on iOS 4.2.1.The phone also featured the newer iOS 2.0.It had bluetooth 2.0 with Wi-Fi.The case was entirely made of plastic unlike its predecessor.Apple sold a million units over the first weekend of launch.It was 12.3mm thick and weighed 133g.

The iPhone 3GS:

The iPhone 3GS
The iPhone 3GS was launched almost exactly a year after the iPhone 3G in June 2009.It featured a faster CPU clocked at 600 Mhz and RAM was upgraded to 256MB.It also had improved download speeds.The screen resolution was same as the previous models but the color depth was increased from 18-bit to 24-bit.It featured an inbuilt magnetometer and had a compass app which was unique at its time.The camera was upgraded to 3MP from 2MP featured on the older models.It featured bluetooth 2.1 and Wi-Fi.It had a thickness of 12.3mm and weighed 135g.Apple sold a million units over the first weekend of launch.

The iPhone 4:

iPhone 4
The iPhone 3GS was succeeded a year later by the iPhone 4.Unlike its predecessors it had a stainless steel frame which served as the device's antenna.It had an Apple A4 processor clocked at 1Ghz and 512MB of RAM.It was available in 8,16 and 32GB variants.The display underwent a major upgrade and now featured a LED backlit LCD display with 960x640 resolution called the "Retina Display".It had a gyroscope which gives precise information about the device's movement in space when combined with the accelerometer.It also featured a front facing camera for video calls and a 5MP rear facing camera with LED flash and HD video recording capability.It was 9.3mm thick and weighs 137g.

The iPhone 4S:

The iPhone 4S:
It was launched in October of 2011,available in 3 variants-16,32 and 64GB and runs on iOS 5.1.1.It retained the design,dimensions and display of the iPhone 4.It featured a faster 800Mhz dual core CPU and had 512MB of RAM.It also features bluetooth 4.0 and Wi-Fi.It also has a new 8MP camera with face recognition and 1080p HD video recording.Apple sold 4 million units in first 3 days of launch.It weighs 140g.It was also the last phone launched during Steve Jobs' lifetime.

The iPhone 5:

Its the latest offering from Apple,featuring a faster processor and a bigger screen for the first time since the original iPhone.It has a 4 inch screen with 640x1,136 resolution with an 16:9 aspect ratio.It runs on iOS 6.0 and is available in 3 variants-16,32 and 64 GB.It has an improved front facing camera and is only 7.6mm thick with a weight of 112g.its powered by an apple A6 SoC  and RAM has been upgraded to 1GB.Newer features include 4G(LTE)data connection and smaller dock connector.


The iPhone has revolutionized the world of smartphones by seamlessly integrating mobile communication and mobile entertainment into a single sleek device wherein the software compliments the hardware.It also introduced uniformity in devices based on a single platform.Finally,the iPhone might not be the greatest phone but its certainly the phone which has challenged and changed the mobile computing industry in recent times.