The making of iPhone

iPhone is a complex piece of device carrying multiple functionality, including Touch screen, video, voice, wireless phone, GPS, Internet, Etc. It is more like a hand held computer than a phone.

Special hardware has been added to the iPhone to make it an effective and powerful mobile device. This includes various sensors, such as an accelerometer and proximity sensor, multi-touch capable screen to support gestures, and of course various radios including GSM, Wi-Fi, and Bluetooth.

In this article the chipset used in iPhone are reviewed and analyzed. iPhone consists of two main boards to carry all the hardware component it needs One board is taken from iPod design and contains application processor (CPU), disk (flash memory), motion sensors and Audio amplifier. The second board contains wireless flash memory, multimedia engine, blue tooth, and WiFi.


Architecture

The iPhone runs a mobile build of Mac OS X 10.5 (Leopard), which is built upon BSD Unix and has many similarities to its desktop counterpart.

Apple has built a custom set of user interfaces around the iPhone to accommodate the proprietary hardware sensors and the use of multi-touch. While the desktop version of Leopard contains frameworks for building windows and common controls, the iPhone version of Leopard has replaced these frameworks with a version tailored for creating simple page-like user interfaces, transitions, and finger-friendly controls such as sliders and picker wheels.

Keyboard caches containing usernames, passwords, search terms, and historical fragments of typed communication. Nearly everything typed into the iPhone's keyboard is stored in a keyboard cache, which can stay in memory for sometime even after deleted.

Screenshots of the last state of an application are preserved, taken whenever the home button is pressed or an application is exited. These are used by the iPhone to create aesthetic zoom effects, and often provide several dozen snapshots of user activity.

The iPhone communicates with a computer via an interface called the Apple File Communication Protocol (AFC). This protocol is a serial port protocol that uses the USB Port and cable when it is connected to the computer and is responsible for things such as copying music and photos and installing firmware upgrades.

Wireless Board

EDGE Baseband Processor - Infineon PM8876 - S-Gold2
S-Gold2 is an advanced EDGE modem technology combined with latest multimedia functions. It is centered around ARM 926 CPU to provide horsepower for complicated, power hungry, software applications. Additionally it hosts on-chip the hardware needed for multimedia features, such as high resolution color display interface, dedicated camera interface for supporting camera applications for up to 2M Pixel, hardware support for MPEG4 encoding, Java hardware accelerator, and large number of connectivity peripherals.

S-Gold2 supports number of applications such as; still pictures and videos, 3D gaming, Java applications, and video streaming. S-Gold2 provides connectivity to Bluetooth, RF radio, WLAN, and A-GPS modules.

Some of it's key modem features include, GSM, E-GPRS, and GPRS multimedia phones, MP3 decoder, Echo cancellation, and Noise reduction.

EDGE MCP including peregrine SP4T RF switch

GSM/EDGE Power Amplifier - Skyworks Sky77340-13

WLAN - Marvel 90-nm 88W8686
This chip carries the WiFi functionality.

Bluetooth - CSR 41B14 - BlueCore4ROM
The bluetooth chip cames from CSR (Cambridge Silicon Radio).

GSM RF Transceiver - Infineon M1817A11

Wireless Flash Memory - Intel PF38F1030W0YTQ2
Wireless NOR Flash Memory (32Mbytes NOR + 16Mbytes SRAM)


iPOD Board

Application Processor (CPU) - Samsung/ARM S5L8900B01 (512Mbit SRAM dice)
The iPhone uses the ARM (advanced RISC machine) processor architecture, originally developed by ARM Ltd. In contrast, a majority of desktop machines use the Intel x86 architecture.

Early reports of the CPU clock speed put the iPhone’s ARM processor running at about 400 MHz with a bus speed at 100 MHz (Hockenberry). It is speculated that the ARM CPU can run at 600 MHz or more but is underclocked to provide for heat dissipation and battery life.

Flash Memory (Disk) - Samsung 65nm 8Gbit NAND Flash (K9MCG08U5M)
This chip is used as the main storage medium in computing and other digital applications. iPhone uses this flash memory just like a hard disk and partitions it, which is based on the Unix OS conventions as well. In order to store files on a hard disk, that raw physical device must first be prepared with partitions, or contiguous sections of a disk to store common groups of information.

There are two partitions on the iPhone. The first partition is 300 MB in size and is the system or root partition(not to be confused with the root folder which will be seen in the second partition). This partition contains the operating system and the default applications that are delivered with a factory fresh iPhone. for the life of the iPhone and contains the default applications and the untampered OS of the device. It contains most of the followings: SMS, Calendar, Photos, Camera, Youtube, Stocks, Maps, Wseather, Clock, Calculator, Notes, Setting, iTunes, Phone, Mail, Safari, and iPod.

The remaining space of the hard disk is partitioned as the user-space (or media) partition. This space is where all music, videos contacts, SMS etc are stored.

Samsung is planning to build 64Gbit multi-level cell NAND flash memory chip based on a 30nm process in 2009. For those not versed in the arts of bits-to-bytes conversion, that's a single chip capable of storing 8GByte of data. A maximum of 16 64Gbit flash devices can be combined to make a 128 Gigabyte memory card that can store 80 DVD resolution movies or 32,000 MP3 music files.

Stereo Audio Codec Processor - Wolfson WM8758BG
This chip is the I2S voice codec. A very good sound quality part, even better than used in iPod.

Motion Sensor - STMicroelectronics LIS302DT
This chip has a sensing element, capable of detecting acceralation using a dedicated process to produce internal sensors and actualtors in silicoln. It is capable of detecting free-fall, motion activated functions, and vibration monitoring.

Apple (NXP) Power Manager
This chip, from NXP (Philips before), is the power manager with the switching power supplies.

USB Battery Charger - Linear Technology 4066
This chip is maily used to charges Single Cell Li-Ion Batteries Directly from USB Port or 5v wall adapter.


Other Parts

Touch Screen: Balda
The Touch Screen is from German manufacturer Balda. There is a SPI multi-touch I/O controller from Broadcom (BCM5973A)

Camera
The camera has a Micron 2Mpixel sensor (MT9D112D00STC).

Display
The display is 320x480, can be a Samsung or AUO module.

Battery
The battery is a Li-IonPolymer 3.7V.

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

The need for Edge QAM

The "Edge QAM" came to existence with Switched Digital Video (SDV). Prior to SDV, QAM modulation was used in cable plants to carry all digital cable services. It sits in hub and is used to move video, voice and data from headends to homes. Each QAM, in a rack-mounted metal box, is capable of carrying 38.8 Mbps of downstream data which is equivalent to one analog channel, 2-3 High-Definition (HD) streams, or 10-12 Standard-Definition (SD) digital video streams.

Even though all QAM use the same architecture, each QAM is dedicated to a specific service. For example, one QAM is used to move Web pages to your cable modem, while another one is assigned to move the digital video channels to your HDTV. Likewise, a QAM dedicated to video on demand (VOD) could not be used for Switched Digital Video (SDV). Hence, the cable operators had to purchase QAM based on services they wanted to provide.

This fundamental issue, created the need for building "Edge QAM", which by definition is capable of carrying both VOD and SDV streams. The next generation Edge QAM will be able to carry IP related services, such as data (Internet service) and voice (VoIP service) in addition to VOD and SDV.

The Players

Some of major vendors of Edge QAM are, Scientific Atlanta/Cisco, RGB Spectrum, Arris, BigBand Networks, Harmonic, Motorola.

The cable operator evaluate the Edge QAM based on three objectives, Price, Density and Openness. With respect to price, currently the QAM are in range on $250. The goal is to reduce to price to $25 range. With respect to density, currently one rack-mounted unit can take between 8-24 QAMs. The cable operators expecting new innovation will increase the density which will ultimately bring the price down. With respect to openness, the cable operator are looking for vendors that eventually can adopt standards protocols.

Functionality

In order Edge QAM move VOD and SDV streams to homes, it needs to communicate with two other device in the network. The "Session Manager", which sets up the linkage between VOD/SDV server and Set-Top-Box and acts upon selecting a channel by viewer. The "Resource Manager", which determines which QAMs are supposed to be moving what stuff and to where. Also see SDV Architecture and IPTV - The software behind SDV for more information.

Currently, the devices are tightly coupled, meaning that they work on propriety protocols. Each manufacturer has developed it's own protocol which makes cable operators bound to purchase set of devices from same vendor. New standard is underway to make the communication protocols between devices consistent. This will create competition among vendors to cut the prices, since cable operators will be able to purchase their devices from multiple vendors. A switch from vendor, a resource manager from another and a session manager from yet a different vendor.

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

Launching and maintaining successful IPTV services

IPTV operation is booming worldwide at a rapid pace. In Europe alone the IPTV subscribers is more than 1.535 millions. Ever since YouTube began demonstrating the potential of the Internet medium, everyone is racing to launch IPTV, which will eventually replace traditional television broadcasting.

Following some fundamental guideline can help launching and maintaining successful IPTV services. The following outlines some of these guidelines:

• Simplicity. Make the services very simple and easy to use. Providing innovative services, but as simple as possible will appeal to a wider audiences covering youngest, Internet savvy generation through oldest grandpa and grandma generations.

• Packaged Services. Triple-Play package provides TV, Internet and voice all in one deal. The triple-play can also bolsters operational continuity.

• Content delivery Services.

1. Content delivery to TV, PC and Mobile devices
   
2. Exclusive content and features for certain viewers with common interest, such as major/minor league football games
   
3. Interactive options to access real-line match stats, such as goal count, attempts, and cards
4. On-demand titles
5. International television programs
   
6. Ability to transfer downloaded content to mobile device
   
7. Hybrid IPTV/Satellite service
   

• Quality of Services. Quality of Service is one of the most important reason for successful IPTV operation. People will not tolerate poor quality of service or any quality inferior to other pay-TV services such as satellite.
  

• Super fast broadband network. FTTH (Fiber-To-The-Home) provides much more bandwidth and enabling ability to offer high-definition, added-value services and whole home distribution. ATT recently introduced Total Home DVR, which allows delivery of five simultaneous high-definition MPEG-4 video streams around the home - two live and three recorded from DVR, for it's IPTV service via copper VDSL network.

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

Attacking IPTV QoE issue

One of the most critical challenges of IPTV cable operators is to provide quality of service to their viewers. Since IPTV uses IP networking mechanism to reach the subscribers, many artifacts of Internet can cause poor Quality of Experience (QoE) to viewers, which leads decreased customer satisfaction and increased customer complains through call centers. It is very essential for IPTV operators to resolve QoE issues, in order to increase customer satisfaction and be able to maintain customers for long run.

A recent study shows that QoE accounts for more than 25% of IPTV adaptation obstacles. The other obstacles include, high subscriber fee - equipment (19%), lack of completing programs (15%), satisfied with existing programs (12%), compelling offers from competitions (11%), high subscriber fee - content (11%), poor customer service and support (6%), others (2%).

One of the most common culprit of poor QoE is packet loss, a normal occurrence in any IP network. packet loss happens for many reasons in variety of different locations. There is no way for an IPTV operator to protect the network against all possible causes and different location of packet losses. many packet losses occur in last mile which makes it even more difficult for IPTV operator to detect and address the problem. The following outlines some of common reasons for packet loss:

• Environmental effect, such as home appliances and electrical public transportation systems
• Congestion which normally happens on prime time viewing time
• Bad wiring at customers premises
  
• Heterogeneous network equipment
• Out of sequence packets
• Duplicate packets
• Core network issues, such as lost network links and route convergence
  

Some other reasons which can impact QoE follows:

• Mismatch TSID to service group configuration
• RF interference on specific frequency/QAM channels
• Reed-Solomon error correction efficiency
• Over-subscription/blocking of SDV QAM channels
• Mini-carousel distribution and configuration
• Grooming/muxing issues at the edge QAM device

Solving packet loss issue

One of the simplest, most effective, and least expensive way of correcting packet loss issue is to deploy a layer of software that detects and corrects the packet losses on the fly from the video stream that is being received by customer. The software recovers the packet losses using an algorithm that generates the missing packets and sends them along with the original video content to customer set-top-box which in turn repairs the video before showing it on the customer's monitor.

The followings outlines some of the benefits this software solution that can bring to IPTV operators:

• Scalability - once installed on the headend, it supports an unlimited number of set-top-boxes
  
• Fixes all loss types, regardless of single or multiple events or where it comes from
• Configurable network overhead, with granularity of one packet
• Configurable latency
  

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

IPTV, the next generation TV

IPTV is becoming more and more popular among cable and telco operators as demand for it is growing very rapidly. IPTV not only provides better advertising solution for the cable operators, it makes it easier for cable operators to be more innovative on pay-TV services. IPTV leverages the IP network to deliver video content to TV viewers using set-top-box, and providing picture quality services.

According to a new research by Gartner, reported on September 25, 2008, the worldwide subscription to IPTV is growing rapidly. Gartner projects the IPTV subscripers will reach 19.6 millions by end of 2008, an increas of 64.1% from 12 millions in 2007.

Worldwide IPTV revenues are projected to total US$ 4.5bn in 2008, an increase of 93.5% from an estimated US$ 2.3bn last year, and go on to reach US$ 19bn in 2012. Approximately 1.1% of households worldwide are expected to subscribe to IPTV services in 2008, and Gartner predicts that global penetration will reach 2.8% by the end of 2012.

One of the reasons for this rapid demand is that the consumer video consumption is increasingly big time.

Portal-based Internet video providers such as YouTube and Joost and over-the-top video providers like Amazon's Video on Demand are also presenting competition for IPTV operators, with some developing their own combined set-top box and video download service, like Netflix and Blockbuster.

Western Europe is found to be the region with the largest number of IPTV subscribers. North America, on the other hand, is identified as the largest market for IPTV revenue.

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

References

IPTV News

Elements of a Web-based Services

Designing web sites that are responsive to customer needs is a critical prerequisite for the success of online services. In this article three primary development aspects of Web-based services are discussed. The common style and architecture used to design Web-based services, Software development methodology, Software management methodology and Internet Routing Protocol.

Building Web Services

One of most common methods of building a Web-based services is REST. Many common Web-based services, such as book-ordering services, search services, online dictionary services, etc - are REST-based Web services. REST is an architecture style (not standard) of networked systems and stands for Representational State Transfer. It was first introduced by Roy Fileding in his PhD dissertation.

The Web is comprised of resources. REST style refers to transferring Web activities from one resource to another till what user (client) is looking for is accessed and provided to user. For example, when a client is looking for a piece of information from a website, by definition of REST, the Web activities present series of hyperlinks that user traverse through till the last piece of information user is interested is displayed. Each of these hyperlinks is a representation of a resource which basically places the client application in a state. Thus, the client application changes (transfers) state with each resource representation.

Although the REST is not a standard it uses the following Web standards

• HTTP
• URL
• XML/HTML/GIF/JPEG/etc (Resource Representations)
• text/xml, text/html, image/gif, image/jpeg, etc (MIME Types)

REST hides the implementation details (e.g., using Java servlets or CGI to implement a Web service) from the client and provides only the "big picture" of the Web to client. The following outlines the characteristics of REST:

• Client-Server: a pull-based interaction style: consuming components pull representations.
• Stateless: each request from client to server must contain all the information necessary to understand the request, and cannot take advantage of any stored context on the server.
• Cache: to improve network efficiency responses must be capable of being labeled as cacheable or non-cacheable.
• Uniform interface: all resources are accessed with a generic interface (e.g., HTTP GET, POST, PUT, DELETE).
• Named resources - the system is comprised of resources which are named using a URL.
• Interconnected resource representations - the representations of the resources are interconnected using URLs, thereby enabling a client to progress from one state to another.
• Layered components - intermediaries, such as proxy servers, cache servers, gateways, etc, can be inserted between clients and resources to support performance, security, etc.
  

Web Service Design using REST method

1. Identify all of the conceptual entities that you wish to expose as services.
2. Create a URL to each resource.
3. The resources should be nouns, not verbs.
4. Categorize your resources according to whether clients can just receive a representation of the resource.
5. All resources accessible via HTTP GET should be side-effect free, that is, invoking the resource should not result in modifying the resource.
6. Put hyperlinks within resource representations to enable clients to drill down for more information, and/or to obtain related information.
7. Design to reveal data gradually. Don't reveal everything in a single response document.
8. Specify the format of response data using a schema (DTD, W3C Schema, RelaxNG, or Schematron).
   

Software Development Methodology

Since the Web-based services are normally based on customer requirement and is subject to change frequently, Agile method is commonly used to develop software. Agile means being able to quickly change direction. Agile method is a method opposed to waterfall model, in which software development is seen as flowing steadily downwards through the phases of requirement analysis, design, coding, testing, integration and maintenance.
Agile methods focuses on working software as the primary measure of progress. It promotes the iterations in software development life cycle and chooses to do things in small increments, with minimal planning, rather than plan at length. This allows responding to the customer needs much faster by adapting changes quickly into the development cycle and minimizing the overall risk. Also the project stakeholders get more involved in the process and at the end of each iteration are updated to provide feedback.

In agile development method, a deliverable and shippable software is developed in a short time frame, also known as "timeboxes". The software developed during each timebox is referred to as an iteration, which normally takes 2-4 weeks. Each iteration goes through full software development cycle, including planning, requirement analysis, design, code, unit test, integration test, QA, demo to product stakeholders and documentations to prepare software delivery to customers. The goal of agile development is to have an available release with minimum bugs at the end of each iteration. It may not add a new functionality to the software. At the end of each iteration, the stakeholders re-evaluate the project priorities with respect to revenue and return on investment. Every agile team has a committed customer representative who makes himself available for developers to answer mid-iteration problem-domain questions.

Managing Agile Software Development Projects

Scrum is one of the methods commonly used to manage agile software development method.

Scrum is a process that includes a set of practices and predefined roles. The main roles in Scrum are the ScrumMaster (project manager), the Product Owner (stakeholders representative), and the Team which includes the developers.

During each development period (sprint), which usually takes two to four weeks, the team creates an increment of a shippable software. The feature set for each sprint is prioritized by Product Owner who informs the team of the items that he wants completed. The team then determines how much of this they can commit to complete during the next sprint.

One of Scrum's biggest advantages is that it is very easy to learn and requires little effort to start using. Following are some general practices of Scrum:

• Customers become a part of the development team.
  
• Like all other forms of agile software processes, Scrum has frequent intermediate deliveries with working functionality. This enables the customer to get working software earlier and enables the project to change its requirements according to changing needs.
• Frequent risk and mitigation plans developed by the development team itself.
• Frequent stakeholder meetings to monitor progress – Balanced (Delivery, Customer, Employee, Process) Dashboard updates – Stakeholders' update – You have to have Advance Warning Mechanism, i.e. visibility to potential slippage / deviation ahead of time.
• No problems are swept under the carpet. No one is penalized for recognizing or describing any unforeseen problem.

Internet Routing Protocol

To connect a client to a Web server, series of routing protocols are used to locate and reach the Web server that can provide the service to client. Some of the most common used protocols are BGP and OSPF.

BGP
Border Gateway Protocol (BGP) is the routing protocol used to exchange routing information across the Internet. BGP is an exterior routing protocol and as such is concerned with routing between networks rather than within them (this is the domain of the interior routing protocols such as RIP, OSPF).

BGP is designed to efficiently manage a large, multi-organisation routing table, such as the global Internet routing table. BGP uses TCP as a reliable transport medium and so it needs only to send out updates when necessary rather than continuously. BGP also has many features to manage routing announcements which are not needed in an interior routing protocol.

On a Cisco router you can configure BGP using the following commands:

router bgp ASN
neighbor neighbor remote-as remote-AS
neighbor neighbor filter-list 1 out
!
ip as-path access-list 1 permit ^$

The main thing to remember is to announce only the networks that you originate or are providing transit to. In general this means applying an AS path filter so that only the NULL path is announced. This avoids announcing all of AAPT's routes to your other provider(s) and then having them use you for transit, which could be expensive! AAPT uses BGP communities (public and private) to control routing announcements, i.e. the routes we send to customers as well as the routes we send to our peers and providers.

OSPF
Open Shortest Path First (OSPF) is an interior routing protocol used within larger autonomous system network in preference to the RIP (Routing Information Protocol), an older routing protocol that is installed in many of today's corporate networks.

Using OSPF, a host that obtains a change to a routing table or detects a change in the network immediately multicasts the information to all other hosts in the network so that all will have the same routing table information. Unlike the RIP in which the entire routing table is sent, the host using OSPF sends only the part that has changed. With RIP, the routing table is sent to a neighbor host every 30 seconds. OSPF multicasts the updated information only when a change has taken place.

Rather than simply counting the number of hops, OSPF bases its path descriptions on "link states" that take into account additional network information. OSPF also lets the user assign cost metrics to a given host router so that some paths are given preference. OSPF supports a variable network subnet mask so that a network can be subdivided. RIP is supported within OSPF for router-to-end station communication. Since many networks using RIP are already in use, router manufacturers tend to include RIP support within a router designed primarily for OSPF.

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.

References
REST-Web-Services
info-connect

iPod Nano, the Genius

Apple just announced the new version of iPod Touch, iPod Nano and iTunes 8. These new products, as announced on 9/9/08, all include a new features called "Genius", which is a new technology from Apple to create playlists based on the song you're listening to and the music in your library in an easy way.

The fourth-generation iPod Nano is only 0.2 inches thick, the thinnest player Apple has ever made. The screen size, however, is kept as previous model. In addition a new accelerometer is built into Nano to enable resizing photos and menus based on the orientation of the player which was available on iPhone and iPod Touch previous models.

The new cool feature "Shake to shuffle", which senses when you shake the player and automatically enters into the shuffle mode. The "Shake to shuffle" feature also uses accelerometer technology.

The user interface of new iPod Nano has much improvements that attempts to solve some of the limitations the Clickwheel has in the iPod Touch and iPhone UIs.

The iPod Nano can play 24-hours of music or four hours of video in a single charge. The prices are set for $149 for an 8G and $199 for 16G.

The new model of iPod Touch has a new look with a curved back, similar to iPhone 3G, kept it's stainless steel as previous iPod Touch model. It's being advertised by Apple as very capable when it comes to play games. The new iPod Touch also has volume control on the side of unit and comes with it;s own build-in speakers. Another fun feature of iPod Touch is a build-in sensor for the popular Nike + iPod system. Unlike the previous model, you can get the shoe attachment and activate the included software.

iPod Touch can play 36 hours of music and six hours of video on a single charge. The prices are set as $229 for 16G and $399 for 32G. The previous owners of iPod Touch may get all new feature by software upgrade and no need to purchase a new unit. The update is free for users who already have the 2.0 version, and $9.95 for users with version 1.

More than 160 million iPods have been sold worldwide since 2004, and sales of the device account for almost 75 per cent of the MP3 player market.

Architecture

The iPod Nano uses general-purpose integrated circuits (IC) instead of smaller, low-cost custom-developed chips, possibly to reduce time-to-market. This design, however, increases the number of electronic components and increases the cost. It uses PortalPlayer PP5021C "system on a chip" with dual embedded 80 MHz ARM 7TDMI processors. It also uses "surface mount technology" which was employed in mobile phones in 2005.

Surface-mounted technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of PCB (Printed Circuit Board).

PortalPlayer is a fabless semiconductor company that supplies system-on-a-chip semiconductor, firmware and software for personal medial players. PortalPlayer was acquired by NVIDIA on January 2005.

Past Incidents

1. In Australia, an iPod Nano flamed up while being charged on a PC.
   
2. iPod Nano set a man's pants on fire while he was working in the Hartsfield-Jackson Atlanta International Airport.
3. In Japan, an iPod Nano sparked while it was still recharging. Apple still is investigating this incident.
4. Last report came out from Japan in August 2008 indicates that 17 incidents of abnormal overheating with 1st-generation iPod Nano units while recharging, causing the cases to catch fire and burn.
   

About me:
bruce atlasi is a professional computer engineer, skilled in telecomm and datacomm technologies and architecture. He has diverse working experience with many telecomm start-ups and fortune 100 companies, including Cisco Systems, IBM, and Siemens. He regularly blogs on About Hi-Tech site.