Sometimes the seemingly simple can become the surprisingly complex. So it was with a teardown of the Esolo MP4 multimedia player. A Portelligent colleague spotted the Esolo in a highway convenience store checkout rack, noting a striking visual similarity to Apple's second-generation iPod Nano. We scooped it up for the princely sum of $40 so we could examine what this decidedly rip-off design used inside. As it turns out, a labyrinthine set of suppliers and murky component identifications leave almost as many questions as answers, but we'll plow ahead in the spirit of curiosity.

External branding of the multimedia player is Esolo, from Esolo Digital, a Houston-based importer who claims to be aligned with "over 100 factories in China." See http://esolodigital.com/ about_us.html for an amusing writeup.

Copying begins with the customer packaging, where a near-identical acrylic case to that used for the Apple original holds both player and accessories of USB cable, headphones (also Apple-esque in design) and a silicon rubber case, something Apple does not include. The USB interface for the Esolo relies on a standard mini-USB connector to the proprietary interface of the "true Nano." As an external cue of product quality, we noted a somewhat crooked USB connector in the Esolo.

External branding of the multimedia player is Esolo, from a Houston-based importer Esolo Digital who claims to be aligned with "over 100 factories in China." Click on image to enlarge.

Disassembly was simple. Removal of two small screws on one of the plastic end-caps allowed the entire electronics assembly to be slid out of the extruded and anodized aluminum shell. Like Apple's design, the manufacturer's logo and other product data is laser etched on the anodized extruded case exterior.

Two circuit boards are held into the slide-out molded plastic tray, connected by a polyimide flex and affixed to the plastic by differing means. The upper board, which supports the display on one side and primary electronics on the other, relies on heat-staking. The lower board, which carries the battery and user-interface (UI) buttons, uses four screws, perhaps in an attempt to better fortify the UI assembly against the rigors of button pushes.

In a departure from Apple, the iconic scrollwheel feature of the original Nano is absent, and five snap-dome keys serve for all navigation. An on-off slide switch along the top of the Esolo is the only other UI feature other than the USB and headphone jacks on the bottom. Another important UI difference is in the display. Apple's use of a bright TFT LCD, which fills the entire display window cut in the Nano case, is substituted here with a 1.4-inch color super-twisted nematic (CSTN) panel surrounded by a generous dark frame of blank space. Hey, cheap means going cheaper.

Battery power is supplied by a single lithium-ion cell operating at 3.7 V with a claimed capacity of 150 mAh. Henry Technology supplies the finished cell, which does incorporate a battery-protection circuit based around a CS213 integrated circuit, the first of many devices that defy ready identification. At least the design uses some form of charge control in a nod to safety.

Despite a feature set that matches and arguably exceeds the Apple Nano given the included FM radio and voice recorder functions in the Esolo, system software is clearly a leg down on Apple's implementation with a very clunky interface and challenging compatibility issues. Still, very few chips are used in the design, and the images provided here are worth comparing with an earlier Under The Hood teardown on the original Apple 2G Nano (see "Revised Nano toughens skin" at www.eetimes.com/193005788) where both component count and PCB sophistication are higher at the expense of manufacturing costs.

Click on image to enlarge.

In the Esolo, the primary ASIC that handles all multimedia and control processing is marked AK1025. Again a search on this part leads to a rabbit-warren of sites discussing mostly firmware hacks for the chip. One such site equates the part to established player Actions Semiconductor's ATJ2091 multimedia SoC part. Actions, based in China and a party in some of its own intellectual-property imbroglios, may have here been copied--Actions' logo and that found on the AK1025 chip share similarities yet are still distinctly different. Either way, the AK1025 supports all MP3, MP4 and JPEG decoding along with the audio CODEC and LCD driver functions on a chip just 3.6 x 3.9 mm in size. Pretty impressive, whoever might be behind the device.

The second chip encountered is clearly associated with the FM radio function and is mounted to a small daughtercard likely used to accommodate FM chip alternatives in the overall design. Package labeling of "RD2008" and "4708" is ambiguous, although the latter is probably a date code. Perhaps the part is a confusingly marked RDA5800 from RDA Microelectronics or CL6010 from Comlent--both Chinese companies doing FM radio chips with matching packages--but the die mark of "CS1000A" would point in a different direction. CreSilicon of Shanghai was founded in 2007 and produces a CS1000 FM receiver that is claimed to be pin- and software-compatible with NXP's TEA5767. Whether the obfuscating package marks are meant to cover a copier's tracks or not is hard to say.

The most clearly genuine component found was the K9LAG08U0B 16-Gbit NAND flash chip from Samsung (verified by die marks), a two-chip stack that provides the 2 Gbytes of storage capacity for the player. Perhaps the challenging margins and manufacturing technology behind high-density NAND keep the smaller players and potential forgers at bay.

Board markings point to Bkeestar (www.bkeestar.com) as the ODM company behind the core board design, at least based on PCB silk-screen legends. Even here, however, one has to wonder if the assembly found in the Esolo was ripped 0ff from Bkeestar, solder-mask legends and all.

Readers may be able to unravel the maze of confusing supply-chain players found here but the outward rip-off of Apple's design would seem to extend to the internals of the Esolo in places. Since the Esolo--and hoard of other media player knock-offs--probably fail to put a dent in Apple's success, the semi-underground world of wannabe gadget and chip makers will probably continue to flourish.

David Carey is president of Portelligent , a TechInsights company. The Austin, Texas company produces teardown reports and related industry research on wireless, mobile and personal electronics.