iPod 3rd Generation Teardown Report - (Paul Halpin 2010)

8/2/2019 iPod 3rd Generation Teardown Report - (Paul Halpin 2010)

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Apple iPod (3rd Generation)

Teardown

Introduction and Lossy Compression background info

Digital audio was made commercially available when CDs emerged on the market, apopular medium storing usually stereo audio in a digital 16-bit format, CDs conventionallyhold 80 minutes of audio, so file size is directly linked to length of the audio; roughly 10Mbper minute for 16-bit 44.1Khz stereo PCM. With newer MP3 players, it is not as simple aslength and size because different types of lossy compression are used, the most popularbeing the MP3 format, which can provide an unnoticeable difference from uncompressedsound at a fraction of the original file size (an MP3 encoded at 128kb/s will have a file sizeroughly 1/11th of the original digital audio), many different compression techniques are

used to achieve this; different psychoacoustic masking models are used to filter outfrequencies in the audio file that are inaudible to human hearing, due to them being aboveor below the audible frequency range or that the particular frequency band is maskedduring the song by another frequency;discarding the excess data in the process.

More modern codecs also supported by the iPod are; The AAC codec, which is aderivative of MPEG-4, similar to MP3 but tests show that AAC can provide an equal orbetter quality Sound file to MP3 whilst retaining or having less file size; optimisedalgorithms are used that are built from the MP3 system.The iPod also supports AIFF and WAV formats - both of which are lossless types - Thesefile types are purely containers for the pure digital audio streams, so if it was ripped directly

from an audio CD, all the original frequencies would be present, at a cost of file size (about32MB for 3 minutes of audio in 16/44.1k format). Another lossless audio format supportedby the ipod is the Apple Lossless audio codec (ALAC), which is like AIFF and WAV, buthas a smaller file size than the latter two; It stores the data in an MP4 container(usually .m4a); it can compress the file size but retain the original data by using a linearprediction algorithm used by other lossless codecs such as FLAC and Shorten.



Dismantling Procedure

1. Prise off the metal casing.

2. Remove ribbon connection from the main board to the hold switch / headphones socket.



3. Lift hard drive carefully so the ribbon beneath is disconnected.

4. Unplug the power cable from the battery to the ipod and remove battery.

5. Unscrew the 6 screws around the main PCB



7. Carefully lift the ribbon connector from the PCB to the board underneath

8. Lift out the PCB to reveal the scroll wheel and LCD electronics.

9. remove LCD ribbon and lift out the LCD screen component.



Portalplayer PP5002

Hard Drive

LCD

Wolfson Codec

DAC

ADCHeadphones/

Line-In

Buttons Memory

Firewire/ USBInterface

DockConnector

LCDAddressing



Other componentsHere, you can see the Li-Ion batteryis connected to the PCB with threewires; the red being positive, theblack negative and the white isactually a 10K negative-temp-coefficient thermistor, which is usedto measure the temperature of thebattery when it is being charged.This particular battery is different tothe one that originally came with theiPod (680mAH), I replaced the oldone with this which has a highermAH rating.

The battery charger is supplied byLinear Technology™ and the Powermanagement chip is provided byPhillips™

The Headphones / Hold switch sectionat the top of the ipod is connected tothe main PCB through a ribbonconnector similar to the battery

connector. The headphone connectorwill have multiple connections to themain board; one each for left and rightaudio channels, which would godirectly to one of the DACs in the iPodand also another connection forground, this is needed to detectwhether any headphones areconnected or not so the ipod knowswhen to auto-pause a track when

headphones are accidentally removedetc.There will be another connection for audio recording because the headphones socketsalso works as a line-in port for third party memo-recording devices, this would require anADC and a compressor of some type before the encoded, recorded audio is stored on theHard Drive.The Hold switch cuts off use of the touch-sensitive buttons on the face of the iPod so thataccidental operation does not occur when the iPod is being carried in a pocket (when thehold switch is in the orange position). This may be a simple case of the hold switch turningoff power to transistors used in the capacitive touch screen so no differences in potentialcan be identified by the touch-button system.



Toshiba 1.8” 40GB HDDKey Features

40GB of data storage for audio filescompact 1.8” formSATA Connection to PCB

The Hard Drive is the main expenditurein the manufacturing of the iPod, it isworth more on its own than the rest ofthe iPod components together. Appleʼsidea when they made the ipod was that

it should be able to hold all of the

songs a customer owns and be able tocarry it round with him/her.The iPod uses algorithms to access theHDD only when it is necessary due tothe fact it is not a solid state componentlike the rest of the ipod parts, thistranslates to high energy consumption.Apple have taken it in their interest to

invest in a large (for the time) memorymodule to temporarily store data fromthe hard drive.Apple made the wise decision to createsoftware not only for their ownoperating system (OS X), but create aversion of iTunes for Microsoft Windowsas well; the majority of computerowners had Windows at the time and itwould certainly increase sales. Thisposed a slight problem to Apple because the OS X OS is not compatible of reading the

NTFS file system used by windows, so the system software in the iPod was changed toread both NTFS and HFS+ file systems - if you were a mac user, your ipod would not workwith windows and vice versa due to the biased file system.Apple made it possible to use the iPod hard drive not only for iTunes music storage, butaccessible as a removable storage media on Macs and PCs, a consumer could store theirphotos and videos etc on the iPod to take to another workstation, but the files would not beaccessible on the iPod itself, just as a storage medium.







AAC, AIFF and WAV formats; the output raw digital audio signalwould be Processed by the sister chip; Wolfson™ WM8731, whichhas a Analogue to digital converter (ADC) and also acts as aheadphone amplifier - Here is a block diagram of the codec fromWolfson™.

This codec system is able to encode MP3 and Audible audio formats from a line-in input inreal time; and it can also decode AIFF, MP3, MP3 VBR, WAV, ALAC, Audible and AACformats.Many reviews of the 3rd generation iPod claim that the bass response of this model isparticularly weak due to the Wolfson™ codec and is mainly a hardware fault.

“The Bass response on the headphones output is seriously flawed due to too small outputcapacitances in the 3rd generationiPod. A Stereoplay.de measurement ofthe 3rd generation ipod confirms thelack of bass”www.stereoplay.de, 2003.

http://www.stereoplay.de/

http://www.stereoplay.de/



Hynix™ HY5V56DKey Features

Small 13.5mm x 8.0mm Package.All inputs and outputs referenced tosystem clock.32MB Random Access Memory

SDRAM

The memory module is provided by Hynix™, a large semiconductor company based inIcheon, South Korea.It has a 256 Megabit memory, when divided by 8 equals 32Mb of memory, which givesmore than enough space for ʻanti-skipʼ insurance; audio files are loaded from the harddrive via the TI™ interface to the memory module, prior to being decoded as they areselected to be played so it works as a buffer, this has two advantages; it stops the hard-drive from being constantly used to prevent physical wear and intense battery usage and itprevents any skipping in the song due to the hard drive being over-accelerated during usee.g. if someone is running/training etc. The compressed sound data is then processed bythe Wolfson™ codec into pure digital form with help from the dual ARM™ processors, it isalso amplified and converted to an analogue voltage that can be translated to soundthrough headphones or speakers.The IC comes in a 54-ball FBGA package soldered to the board, it has an operating

voltage of 3.3±0.3V

Texas Instruments™ TSB43AA82Key Features

Single 3.3V supplyInternal 1.8V circuit - reduces Power consumptionIEEE 1394 (Firewire 400) FunctionsSupports ATAPI and SCSI modes40MHz Clock Speed144 Pins8-/16-Bit Asynchronous and Synchronous DMA

Interface

This chip by Texas Instruments™ provides the interface between the PortalPlayer™, theHDD and also provides the FireWire drivers, through which the iPod charges andexchanges data with the Mac/PC. This is a main feature of this iPod that other MP3players of the time did not have; firewire connectivity was an exclusivity of Apple™ andboasted faster data transfer than USB 1.1 and 2.0. In reality, the data transfer rate islimited not by the data capacity of the cable itself, but the speed of the Hard Drive (in the

case of this iPod, 5400RPM) in both the iPod and the host (either PC or Mac) and also thisparticular chip that handles the interfacing of external entities. The iPod also has its battery





data transfer - newer iPod models can take advantage of the external current from a PC tocharge the battery, this can only be achieved when using a firewire connection on thisparticular model. This chip converts the SATA interface of the hard drive to one that can beread by the USB port of the PC/Mac, USB uses less bandwidth than the SATA interfaceand cables are usually smaller in USB, SATA cables are sometimes large and flat ribbons,SATA uses more power/current to transfer data at higher speeds.

Phillips PCF50605HN™Key Features

This chip manages the power throughoutthe ipod, There is not much information onthis chip, but i believe it is used to supplydifferent levels of DC voltage to differentcomponents in the iPod as it is required.this could be achieved by a network ofresistors and logic gates and latches etc, it

prevents the components from overheatingor having the wrong voltage sent to them.This chip could also give all thecomponents a common ground reference.



Components Costs

Component / Process Rough Cost Percentage

Hard Drive - Toshiba JPN $140.00 61%

Memory Module - HynixKOR

$30.00 13%

Inputs / Outputs - Various $25.00 11%

LCD Module - Unknown $15.00 7%

Audio processor - Wolfson $6.00 3%

PortalPlayer™ CPU $5.00 2%

Assembly and Test - Labour $3.00 1%

Battery Pack $3.00 1%

Display Driver $2.00 1%

VAT 17.5% $40

Shipping & Insurance $8

Import Tax $40

Components/AssemblyTotal:

$229.00 100%

Total expenditure $317

RRP: $499.00

Rough Profit: $182



Product Design and ConclusionApple is renowned for their stylish and modern designs in consumer electronics and theiPod (third generation) is no exception, the design and human interfacing of the device hasbeen greatly improved over previous models of the iPod, The first generations had amechanical touch wheel, whereas this model uses a calibrated capacitive touch screenand an array of buttons that use the same technology for human interfacing.Appleʼs trademark minimalist white design has been used so that it is uniform with the restof their trademark, many consumers see this as a fashion icon and buy iPods purely forthe brand name.Many customers will see a new iPod model as a must have gadget, iPods always takeadvantage of the current highest technologies that are available to consumer level, thenewly designed touch buttons and red backlight are a different take on the iPod design,but stylishly in-keeping with the Apple flair.

Apple must have had many different teams working on the iPod model, for different partsof the device, at one point they would have merged together to discuss howe they could fitall the various components into a small, reliable, ergonomic design.I believe the iPod is an excellent MP3 player with accurate sound and a stylish exteriorand is still the top of the market today.

http://www.applematters.com/assets/images/uploads/old/products/cache/ 3G_ipod_in_dock_300x422.jpg

http://www.applematters.com/assets/images/uploads/old/products/cache/3G_ipod_in_dock_300x422.jpg





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iPod 3rd Generation Teardown Report - (Paul Halpin 2010)