Figure 3 Back-panel perspectives of Access HDs DTA-1080D (a), Apex Digitals DT502 (b), Dish Networks TR-40 CRA (c), and Sansonics FT-300A (d) reveal the hardware enhancements that Apex Digitals product provides.

N HA N ED

o segment of the electronics industry is immune to competition, but skirmishes in the consumer-electronics segment are arguably among the bloodiest. Scant per-unit profit margins are the norm, not the exception, and, therefore, manufacturers rely heavily on robust volume shipments as the path to fiscal triumph. The difference between a runaway success and a never-left-the-runway failure sometimes hinges on the slimmest of feature, price, and other differentiators, and potential customers notorious fickleness is no guarantee that what works today will continue to appeal for the next product generation or even for the next week.
Take CECBs (coupon-eligible converter boxes), for example. The intent of the US-government-funded CECB program is to ensure that individuals without access to alternative television services, such as cable, satellite, or IPTV (Internet Protocol television), and lacking the funds necessary to purchase a full-featured ATSC (Advanced Television Systems Committee) set-top box or ATSC-supportive television can still access over-the-air, freethat is, advertising-supportedtelevision. Access to such programming is arguably a citizens right and contributes to the common

-ON PRO

By Br i a n D i p e r t S e n i o r Te c h n i ca l Edi tor
The pending NTSC shutoff has US consumers clamoring for rebate-eligible hardware that will stave off the loss of over-the-air television. How do manufacturers distinguish themselves from opponents in such a hypercompetitive market?

The ATSC couponeligible

converter box:
a consumer-electronics case study
20 EDN | february 5, 2009
good by virtue of the broadcast of emergency alerts, government policy sessions, election debates, and the like. CECBs whose retail price comes close toor matchesthe $40-per-coupon, at two coupons per request, government-rebate amount translate to a free or nearly free end-customer expense. Perhaps not surprisingly, those CECBs will likely constitute the lions share of all CECB sales. The $40 price needs to comprehend not only BOM (bill-of-materials), development, and manufacturing costs, but also shipping and warehousing expenses, along with distributor and retailer markups. With these criteria, theres seemingly no opportunity for differentiation, but creative engineers and their marketing counterparts have nonetheless still managed to create a diverse product smorgasbord. How? Four products provide case-study examples. A program backgrounder The CECB program aims to provide continued broadcast-television recep-

AT A G L A NCE

Given a free or nearly free afterrebate target, design engineers and their marketing partners have multiple paths to potential success.
Even considering the NTIAs (National Telecommunications and Information Administrations) stringent list of dos and donts necessary for CECB (coupon-eligible-converter-box) certification, several companies have discovered differentiation possibilities through hardware, software, or both. Single-chip integration doesnt necessarily translate to design superiority, especially in non-spaceconstrained applications and when you factor in costly heat sinks. The designs in this article dont indicate strong endorsements for silicon tuners claimed abilities to deliver tangible benefits over their can predecessors.
featured ATSC-cognizant gear. In developing the program, the US government strove to avoid excessively burdening the taxpayers who finance it (references 1 and 2). According to the NTIA (National Telecommunications and Information Administration) program-managing organization, CECBs cannot offer high-definition video-output capabilities; this constraint disallows HDMI (high-definition-multimedia-interface), DisplayPort, DVI (digital-visual-interface), RGB, and component-video outputs. It even disallows the 480p (480line progressive-scan) video mode, as well as digital audio or greater-than-twochannel analog-audio outputs. CECBs also cannot support encryption-free

tion for those who, for geographic or financial reasons, cannot access alternative TV services or purchase full-
Figure 1 Multiple paths to a $40or $40.01retail price point include Access HDs DTA-1080D (a), Apex Digitals DT502 (b), Dish Networks TR-40 CRA (c), and Sansonics FT-300A (d). Sansonics retail partner, Meritline, even included an Artec AN2 antenna (e).
Table 1 CECB key specifications
Product Access HD DTA-1080D Apex Digital DT502 Dish Network TR-40 CRA Sansonic FT-300A After-rebate price 1 cent 1 cent Free Free Chassis construction Plastic Metal Plastic Metal Dimensions (width

3height3depth) (in.)

531.2535.25 931.7536 631.2534.5 73135
Bundled accessories User manual, coaxial cable, remote control and batteries, wall wart User manual, coaxial cable, remote control and batteries, analog audio/composite video cable, ac power cord User manual, coaxial cable, remote control and batteries, wall wart User manual, coaxial cable, remote control and batteries, wall wart, antenna
february 5, 2009 | EDN 21
Figure 2 Notable internal disparities magnify noticeable exterior differences among Access HDs DTA-1080D (a), Apex Digitals DT502 (b), Dish Networks TR-40 CRA (c), and Sansonics FT-300A (d). Note that the excess thermal paste in the area surrounding the DT502s Realtek RTD2885 was the inadvertent result of my removal and replacement of the SoCs passive heatsink; the excess paste was not present when the CECB originally came to me.
clear QAM (quadrature-amplitude modulation) for cable-television support. Simply stated, CECBs strictly convert ATSC to NTSC (National Television System Committee) for legacy-TV compatibility. These stringent restrictions couple with equally stringent requirements, such as a host of broadcast-reception and de-
coded-video minimum-quality specifications that the NTIA tests before giving a product the CECB blessing. Units must be capable of both center-cropping and letterboxing a 16-by-9-aspect-ratio program for compatibility with 4-by3-aspect-ratio displays. They must offer composite video and two-channel analog-audio outputs, as well as a merged
audio-plus-video RF output (Reference 3). They must also include a dedicated remote control and offer compatibility with universal remotes. Bit-stream compatibility extends beyond basic MPEG-2 (Moving Picture Experts Group) video and Dolby Digital audio to additionally comprehend EAS (emergency-alert-system) messages, V-chip rating descriptors,
Table 2 CECB prominent ICs
Product Access HD DTA-1080D Apex Digital DT502 Dish Network TR-40 CRA Sansonic FT-300A Tuner Microtune MT2131 (silicon) Samsung DTVS22D (can) Thomson DTT76809 (can) Microtune MT2131 (silicon) Demodulator Decoder DRAM Zentel A3S56D40ETP Nanya NT5DS16M1CSS Hynix HY5DU121622DTP Etron EM6AA160TS Flash memory Spansion SPI Spansion SPI Spansion parallel interface SPI Zoran SupraHD 741 Realtek RTD2885 STMicroelectronics STV0373 Auvitek AU8515 STMicroelectronics STi7707WUDP ALi M3601C

22 EDN | february 5, 2009
and closed-captioning info, along with PSIP (Program and System Information Protocol) data. And CECBs must burn no more than 2W of power with audio and video outputs disabled, as well as support automatic power-down capabilities. The differentiation-cultivating gap between what the converter must include and what it cannot include still ends up being broader than at first glance. Some companies choose to use higher-quality chassis-construction materials or make other cosmetic enhancements. Others bundle additional accessories beyond the minimum set that converter-box specifications dictate. Some vendors offer added hardware-delivered features, and others add capabilities through software. And then there are those manufactur-
Table 3 CECB software-enabled additional features
Product Access HD DTA-1080D Apex Digital DT502 Dish Network TR-40 CRA Sansonic FT-300A Electronic program guide 10 hours Full and list Full (grid) Current (banner) Digital closedcaption decoding Yes Yes Yes No Multilingual menus Yes Yes No No Reminders No Yes Yes No VCR timer No No Yes No
ers that choose none of these differentiating paths; instead, they build a barebones set-top box that stays within the NTIA boundaries in all regards. Because theres little to no marketing motivation to sell a CECB for less than $40, these companies end up with a wider-
than-average disparity between BOM cost and price. By passing along some or all of this incremental profit to distributors and retailers, they cultivate a retailshelf-space preference for their products, thereby creating consumer demand by squeezing competing alternatives off re-
Figure 3 Back-panel perspectives of Access HDs DTA-1080D (a), Apex Digitals DT502 (b), Dish Networks TR-40 CRA (c), and Sansonics FT-300A (d) reveal the hardware enhancements that Apex Digitals product provides.
But how well do they work?
This article intentionally omits hands-on analysis of the four CECBs (couponeligible converter boxes) operational capabilities: reception robustness, audio and video quality, and user-interface comprehensiveness and responsiveness, for example. I still plan, however, to pass along such data online. Also, every reception situation is unique. Although the impressions I ascertained at my home office might provide useful information, they would by no means provide a definitive examination of each settop box. And, even at my location, reception characteristics are a moving target. The ABC affiliate in Reno, NV, for example, plans to move its digital broadcast from VHF Channel 9 to Channel 8 on the NTSC (National Television System Committee) shutoff date, a migration that I hope will improve my ability to tune it in. Regularly visit my blog and look for write-ups with The ATSC couponeligible converter box in the titles, thereby identifying them as Web-site-published addendums to this print piece. Among them, youll also find high-resolution close-up images of the CECBs interiors available for download, pinpointing specific ICs. Additionally, augment your EDN research at the AVS Forum (www.avsforum. com). This tech-enthusiast nirvana is teeming with information from folks passionate about video in all of its myriad forms, and the information will both get you quickly up to speed and provide you with a comprehensive set of impressions on each CECB youre considering. For example, as of midDecember, just one of the several active discussion threads on Dish Networks TR-40 CRA was more than 180 pages long, with each page containing several dozen posts.

february 5, 2009 | EDN 23
+ See the The ATSC coupon-eligible
converter box posts at www.edn.com/ briansbrain for supplemental information on this articles topics.
converter, easing its use in vehicles, for example. Building blocks Considering my pleasure with the assembly and accessorizing diversity I discovered upon opening the four products packaging, you can imagine how much more thrilled I was when I popped off the set-top boxes chassis panels and encountered four different IC assemblages (Figure 2 and Table 2). Beginning with the tuner, the initial piece of silicon that the incoming ATSC signal encounters, I found that the Apex Digital DT502 and Dish Network TR-40 CRA employ traditional can tuner modules from Samsung and Thomson, respectively. A brief glance at the Access HD DTA1080D and Sansonic FT-300A might suggest that theyre also can candidates, but they arent. Both boxes use Microtunes MT2131 silicon tuner, albeit in a can-compatible-subsystem form factor that suggests that manufacturing-time comparative price and availability assessments rather than an inherent silicontuner technical advantage drove the IC selection on the systems PCBs (printedcircuit boards). The next two steps in the ATSC-processing chain are demodulation of the bit stream from its UHF or VHF carrier and decoding the audio, video, and other digital data. Two of the four CECBs, the Access HD DTA-1080D and the Apex Digital DT502, employ a single SoC for both tasks; respectively, Zorans SupraHD 741 and Realteks RTD2885. Not coincidentally, I suspect, these units were the only two set-top boxes I analyzed that incorporate cost-incurring passive heat sinks. On the other end of the integration spectrum, Dish Networks TR-40 CRA leverages an STMicroelectronics STV0373-demodulator and STi7707WUDP-decoder chip set. Sansonics FT-300A also uses separate ICs, but the demodulator companion to the Acer Laboratories M3601C decoder is not visible upon initial PCB inspection. Enthusiast-generated Internet documentation claims that the FT-300A employs Auviteks AU8515 demodulator; I suspect that it is alongside the Microtune MT2131 within the can enclosure that Sansonics manufacturing partner, Falcon Digital, designed (Reference 4). The set-top boxes memory archi-

+ Go to www.edn.com/090205df to post a comment on this article. + For more technical articles, go to www.edn.com/features.
tail shelves. By happy accident, the four CECBs that this article analyzes exemplify all of these strategies. Chassis and accessories The CECBs this article showcases came from the two coupons I requested for my home-office residence, along with two I obtained from a friend. I based my CECB selection on the devices cosmetic differences, in the hope, which panned out, that these dissimilarities would translate to fundamental design distinctions (Figure 1). From CompUSA, I first acquired Access HDs DTA1080D and Apex Digitals DT502, each for 1 cent after rebate. The two boxes exemplify radically different product strategies; the DTA-1080D includes scant extras: a remote control and two batteries, a wall-wart external ac/dc converter, a slender sheath of paper documentation, and a short coaxial cable. The embedded-power-supply DT502 also comes with a composite video-plus-two-channel-analog-audio cable bundle. And, whereas the DTA-1080D is small, plastic, and conjoined by plastic clips, the larger DT502 offers sturdier metal sheets held together with screws (Table 1). The other two set-top boxes are equally diverse in both design and decor. The free-after-rebate TR-40 CRAa CECB you can get from Dish Network (as I did), EchoStar, or Sling Mediais reminiscent of the DTA-1080D in assemblythat is, plastic, albeit this time held together with metal screwsexternal power supply, and scant accessory apportionment. Although the metalfabricated Sansonic FT-300A, which I obtained free after rebate from Meritline, doesnt include a DT502-reminiscent analog audio/video cable, the company instead thoughtfully includes a flat Artec AN2 antenna. Like the Access HD and Dish Network units, Sansonics CECB also employs an external ac/dc
24 EDN | february 5, 2009
tectures also beg for some degree of discussion. They all use a single DDR400 SDRAM with a 16-bit system interface, albeit in a diversity of densities and from a diversity of sources: Etron Technologys 256-Mbit SDRAM (in the FT-300A), Hynix Semiconductors 512Mbit SDRAM (in the TR-40 CRA), Nanya Technologys 256-Mbit SDRAM (in the DT502), and Zentel Electronics 256-Mbit SDRAM (in the DTA1080D). Three of the four CECBs employ eight-lead SOIC-packaged SPI (serial-peripheral-interface) flash memory for system code, in two cases from Spansion. The fourth CECB, Dish Networks TR-40 CRA, instead uses a BGA-packaged parallel-interface burst-mode flash memory, also from Spansion. Although all four STBs implement in-system-upgradable firmware potential, none of them offer a means of enabling consumers to do the upgrades themselves. Internet forums are therefore rife with posts from CECB owners attempting to discern units with latest and greatest firmware versions through product-code and manufacturing-location data, as well as from folks complaining about the need to ship CECBs back to manufacturersat customer expense and with lengthy servicing delaysfor updates to fix bugs and add features (see sidebar But how well do they work?). enhancements The NTIA-defined gap between what features the box must include and what it cant include might be slender, but it does exist. A glance at the CECBs back panels reveals the hardware-based augmentation that Apex Digital chose to include: a higher-quality, albeit still 480line-interlaced S-video output, along with Smart Antenna array compatibility (Figure 3). And all four STBs support analog pass-through mode, enabling their owners to continue to receive signals from low-power stations and regional translator transmitters, neither of which are required to cease their NTSC broadcasts this year. Software support can enable additional CECB capabilities, assuming that the system contains a sufficiently robust host CPU and adequate memory resources (Table 3). They include a variable-duration electronic program guide, digital closed-caption-decoding support,

F o r M o r e I n f o r m ati o n
Access HD www.accesshd.tv Acer Laboratories www.ali.com.tw Apex Digital www.apexdigital.com www.apexdtv.com Artec www.artec.com.tw Auvitek www.auvitek.com CompUSA www.compusa.com www.systemax.com Dish Network www.dishnetwork.com Dolby Laboratories www.dolby.com EchoStar Technologies www.echostar.com Etron Technology www.etron.com Falcon Digital www.falcondgt.com Hynix Semiconductor www.hynix.com Meritline www.meritline.com Microtune www.microtune.com Nanya Technology www.nanya.com NTIA (National Telecommunications and Information Administration) www.ntia.doc.gov www.ntiadtv.gov Realtek www.realtek.com.tw Samsung www.samsung.com Sansonic www.sansonic.net Sling Media www.slingmedia.com Spansion www.spansion.com STMicroelectronics www.st.com Thomson www.thomson.net Zentel Electronics www.zentel.com.tw Zoran www.zoran.com
multilingual menus, viewer-reminder notifications of pending programs, and timer-based control of both system operating modestandby or activeand the channel you are tuning in, so a VHS or DVD recorder, for example, can capture the CECBs output.EDN R e fe r e nce s
Dipert, Brian, ATSC: What do you see? EDN, March 26, 2008, www.edn.com/blog/400000040/ post/1460023946.html. 2 Dipert, Brian, NAB 2008: ATSC set-top updates, EDN, April 15, 2008, www.edn.com/blog/400000040/ post/1710024971.html. 3 Dipert, Brian, A crash course in color conversion, EDN, June 7, 2001, pg 46, www.edn.com/article/CA85641. 4 http://en.wikipedia.org/wiki/ Comparison_of_CECB_units.
You can reach Senior Technical Editor Brian Dipert at 1-916-760-0159, bdipert@edn.com, and www.bdipert.com.