Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
?
EE Times-Asia > Processors/DSPs
?
?
Processors/DSPs??

Apple TV animates living room experience

Posted: 08 Jun 2007 ?? ?Print Version ?Bookmark and Share

Keywords:Apple TV? Apple TV teardown? digital media? Ethernet? Wi-Fi?

Having conquered the market for portable media players, Apple marches on toward the living room. Apple's computers remain a distant second in market share to the Windows-powered PC (though they've shown some recent strength), but the iPod has won its product category hands down.

Now Apple, having stripped "Computer" out of its name, is targeting wireless distribution to the home via the Apple TV. The goal is to move digital media from the "lean forward" world of the computer to the "lean back" environment of the home television. The irony is that the Apple uses a pared-down computer to get there.

TV-computer box?
Characteristically, Apple's setup instructions for the Apple TV are dead simple: "Download, synch, watch." I haven't yet tried the Apple TV, but other experience with the company's goods would suggest that the startup process is as relatively pain-free as promised.

The box itself measures a modest 197-by-197-by-28mm, so no major real estate will get consumed in anyone's home theater setup. An I/O panel on the back of the unit sprouts connectors for Ethernet, a hobbled USB interface, HDMI, component video, RCA-jack audio and optical audio, while the front panel has only a small window for the IR remote control. The Apple TV adheres to the industrial design aesthetic evident in such other Apple products as Airport Extreme and the Mac Mini.

The platform uses 802.11g or 802.11n wireless to handle the transfer of movie files from the iTunes environment. Of course, it requires that the host computer with iTunes have the same wireless support, though 10/100Mbps Ethernet is available as a wired alternative for connectivity. It's worth noting that the iTunes requirement here does not necessarily mean an Apple computer must be used, since iTunes works with both the Mac and Windows OS.

Unlike some other Apple products, the Apple TV was easy enough to open, with corner Torx-head screws tucked underneath the adhesively attached rubber anti-skid bottom surface.

A 40Gbyte 2.5-inch hard drive is bolted to the floor panel of the Apple TV, serving as the mass storage for holding local copies of iTunes content. A Fujitsu MHW2040AT was used in the unit analyzed here, but multisourcing would leave other vendor options available to Apple given the seemingly generic nature of the drive. Indeed, outside of Apple, clever entrepreneurial types have already started offering disk swaps to increase storage capacity, further supporting the notion of a standard hard drive interface.

The electronics in the Apple TV consist of a single "motherboard," an 802.11a/ b/ g/n plug-in daughtercard and a power supply brick assembly to convert the 120Vac input to a 5Vdc (7.2A) supply rail. The use of the term motherboard is fitting here because, in many respects, the Apple TV is really a connected PC. Despite the Apple TV's focus on a media adapter function, the component set is really a scaled-down computer, with a CPU, graphics adapter, I/O controller, memory hub and ports for Ethernet, Wi-Fi and USB.

Intel inside
As for the suppliers of those key "hidden PC" functions, the CPU comes from Intel, in a move consistent with Apple's recent migration to that company's processor elsewhere in its computer lineup. Given the Apple TV's use of an OSX operating system derivative, the CPU selection here is of little surprise. While the part number etched on the Intel die (7645A966) does not provide a lead to a specific Intel part number, others have concluded that the component is Intel's Crofton variant of the Pentium-M family, running at 1GHz. Dedicated hackers (you folks are amazing!) have already devised ways to boot a full-blown OSX and run the Apple TV as an ordinary Apple computer, albeit with modest horsepower.

Apple TV from Apple

Apple's setup instructions for the Apple TV are dead simple: "Download, synch, watch."
(View Apple TV's teardown diagram)

The I/O controller also is provided by Intel, in the form of the PC82801, joining up with the Intel QG82945 graphics/memory hub controller. The GHMC is coupled to four Nanya 64Mbyte DDR2 memory chips (again almost certainly interchangeable with other manufacturers' chips) for a total of 256Mbytes of system memory. The Intel I/O chip interfaces with the hard drive, a USB controller from Cypress Semiconductor (the CY7C63823) and a 10/100Mbps Ethernet controller from Realtek (the RTL8100C). While the USB port is nominally restricted to use for diagnostics, the hacker community has devised workarounds to open up the USB port to accept mice, keyboards and other USB peripherals.

Nvidia provides the graphics processor: the GeForce 7300, supported by 64Mbytes of graphics memory in the form of two 32Mbyte of Graphics DDR3 SDRAMs from Samsung (K4J55323QG). The Nvidia chip handles all of the video processing and scaling between native iTunes video and the 1080i 60/50Hz, 720p 60/50Hz, 576p 50Hz (PAL format) or 480p 60Hz output options.

While the Nvidia chip handles output to the Apple TV's composite video jacks, a separate Silicon Image SiI1930 chip provides interface to the HDMI output option. Audio support comes from a Realtek ALC885 audio codec; that device, with a small amplifier, drives the stereo audio ports.

A clock generator from Cypress (CY28445), an Intel-specific power controller from Intersil (ISL6218) and a small MCU from Silicon Storage Technology (SST89V54RD2) join with various smaller-scale power management and memory components to complete the major motherboard component set.

Wirelessly connected
The 802.11 Wi-Fi adapter card is a plug-in moduleperhaps a surprising decision, since motherboard-based placement could have allowed a pinch of cost reduction. Technical as well as business issues may have driven the decision to keep the function separate.

Isolating the wireless function potentially allows the wireless card to be multisourced. While saving a connector and a few parts may reduce cost locally, the impact of potential competition can work wonders in improving overall vendor pricing on a much larger scale.

A technical benefit of the Wi-Fi daughtercard is simply the ability to upgrade the wireless functionality independently of the balance of the Apple TV design. But this has a business-oriented upside as well, given Apple's penchant for secrecy.

On the fast-moving wireless front, the next big thing can come along in a hurry. If a separate Wi-Fi module is used, only that module needs FCC certification--along with the requisite early visibility in component makeup. Thus, the FCC certification documents would reveal the attributes of the wireless connection only; the Apple TV's full makeup would be known only after launch.

The Wi-Fi module here is based on a two-chip solution from Broadcom in which the BCM4321 baseband/MAC chip joins up with the BCM2055 transceiver. Much of the technical complexity and multiband diversity of the RF front-end is hidden within SiGe Semiconductor's SE2545A front end, which uses multichip packaging to bring in two dual-band transmit/receive chains, power amplifiers, power detectors, switches, diplexers and matching.

Next living room king?
The Apple TV takes an important next step in Apple's desire to become a bigger part of home infotainment. As the analysis here and hacker efforts elsewhere have shown, the Apple TV is essentially another Mac, stepped down in performance to meet the needs of a wireless media adapter.

It's too early to tell whether the intended consumers will embrace the media distribution model on which the Apple TV is based. In the meantime, the technologically adventuresome have another toy to play withprovided they're willing to void their warranty.

By David Carey
President, Portelligent




Article Comments - Apple TV animates living room experi...
Comments:??
*? You can enter [0] more charecters.
*Verify code:
?
?
Webinars

Seminars

Visit Asia Webinars to learn about the latest in technology and get practical design tips.

?
?
Back to Top