Power supply In Mobile Phone
Mobile phones generally obtain power from rechargeable batteries. There are a variety of ways used to charge cell phones, including USB, portable batteries, mains power (using an AC adapter), cigarette lighters (using an adapter), or a dynamo. In 2009, the first wireless charger was released for consumer use.
Development and adoption of a common charger solution
On 17 February 2009, the GSM Association (GSMA), together with 17 mobile phone manufacturers and providers, announced their commitment to implementing a cross-industry standard for a universal charging solution for new mobile phones. The standard charger connector to be adopted by manufacturers in the Open Mobile Terminal Platform (OMTP) including Nokia, Motorola and Samsung is the micro-USB connector (several media reports erroneously reported this as the mini-USB). The new chargers will also be much more energy efficient than existing chargers. Having a standard charger for all phones means that manufacturers will no longer have to supply a charger with every new phone. The OMTP technical requirements describe a common charger with a standard USB-A receptacle and a detachable USB-A to microUSB-B cable.
In October 2009, the International Telecommunication Union (ITU) announced that it had also embraced the Universal Charging Solution standard – based on the OMTP specifications promoted by the GSMA – as its “energy-efficient one-charger-fits-all new mobile phone solution,” and added: “Based on the Micro-USB interface, UCS chargers will also include a 4-star or higher efficiency rating — up to three times more energy-efficient than an unrated charger”.
Common power supply standard in the European Union
In 2009, many mobile phone manufacturers signed a Memorandum of Understanding (MoU), agreeing to make most new data-enabled cell phones marketed in the EU compatible with a common External Power Supply (EPS). All signatories agreed to develop a common specification for the charger “to allow for full compatibility and safety of chargers and mobile phones.” The technical specifications for the common EPS were published in December 2010 as EN 62684:2010, “Interoperability specifications of common external power supply (EPS) for use with data-enabled mobile telephones.” The mobile phone manufacturers who have agreed to this standard include the original signatories Apple, LG, Motorola, NEC, Nokia, Qualcomm, RIM, Samsung, Sony Ericsson, and Texas Instruments as well as Atmel, Emblaze Mobile, Huawei Technologies and TCT Mobile (Alcatel). The Memorandum of Understanding also provides for the use of the common External Power Supply with compliant phones not equipped with a MicroUSB receptacle: “4.2.1 … if a manufacturer makes available an Adaptor from the Micro-USB connector of a Common EPS [External Power Supply] to a specific non-Micro-USB socket in the Mobile Phone, it shall constitute compliance to this article.”
Common power supply standard in the People’s Republic of China
In 2006, the People’s Republic of China issued a standard for mobile device power supplies (based on a 5V Power Supply with a USB-A receptacle and a detachable cable). The 2006 regulation is flexible regarding the interface on the mobile phone itself, allowing for the use of adapter cables if the mobile device is not equipped with a standard USB connector. The standard was revised in December, 2009 (CCSA YD/T 1591–2006 updated to YD/T 1591–2009).
Common power supply standard in South Korea
In 2001, the South Korean Telecommunications Technology Association (TTA) released a “Standard on I/O Connection Interface of Digital Cellular Phone” TTAS.KO-06.0028. The main feature of the standard is the specification of a 24 pin connector / socket for mobile phones sold in Korea. The 24 pin connector handles power input (battery charging) and power output, as well as data communication (USB and other digital signals), analog audio inputs and outputs (for hands-free microphone, earphone) and other signals. The 2007 revision of the standard (TTAS.KO-06.0028/R4) specifies a smaller 20 pin connector to succeed the 24 pin connector.
Charger efficiency
The majority of energy lost in a mobile phone charger is in its no load condition, when the mobile phone is not connected but the charger has been left plugged in and using power. To combat this, in November 2008, the top five mobile phone manufacturers Nokia, Samsung, LG, Sony Ericsson, and Motorola set up a star rating system to rate the efficiency of their chargers in the no-load condition. Starting at zero stars for >0.5 W and going up to the top five star rating for <0.03 W (30 mW) no load power.
A number of semiconductor companies offering flyback controllers, such as Power Integrations and CamSemi, now claim that the five-star standard can be achieved with use of their product.
Battery
Formerly, the most common form of mobile phone batteries were nickel metal-hydride, as they have a low size and weight. Lithium ion batteries are sometimes used, as they are lighter and do not have the voltage depression that nickel metal-hydride batteries do. Many mobile phone manufacturers have now switched to using lithium–polymer batteries as opposed to the older Lithium-Ion, the main advantages of this being even lower weight and the possibility to make the battery a shape other than strict cuboid.Mobile phone manufacturers have been experimenting with alternative power sources, including solar cells. A prototype mini solar panel from Wysips was able use perfectly as ‘live phone’ with Android phone. The mini solar panel can be installed on the Android phone screen, although the phone battery is still needed due to the solar panel solely has not been able to produce enough energy.