Let’s Put a Set-Top Box on a Chip

The next time you sit down to watch the baseball playoffs or get caught up on the latest news, stop and think about your television for a minute. What if you were to take all those components, all those wires, and all those connections, shrink them down, and put them on one piece of silicon?

At first glance, it’s hard to imagine. But if you think about it, it's possible to do.

Fiber optic cable connections that provide TV and Internet could profit from higher levels of integration. In some cases, the fiber cable comes right into your house. In other cases, it stops at the street and the medium changes from fiber optic to coaxial cable. In both cases, there is a box full of electronics that does massive amounts of signal processing.

Wherever the fiber optic cable has its termination point, there will be an optical receiving device such as a photo diode; that will be followed by a transconductance (or perhaps a transresistance) amplifier. Since this is a duplex system, there will also be a laser diode and its associated driver.

(Source: Maxim Integrated, the sponsor of this site)

(Source: Maxim Integrated, the sponsor of this site)

The driver, of course, contains an output capable of sourcing current in the range of a few hundred mA to an amp or two (pulsed). There is also feedback circuitry to regulate the output accurately and possibly to monitor the laser diode's temperature.

If there is a coaxial cable link to the house, then we need driver and receiver circuitry. If we stop right there, we have plenty that we could try to push into one piece of silicon. Is that possible? Practical?

If the fiber optic cable comes right into the house, then everything described above would be in what's commonly referred to as the set-top box. But there's more, of course. There will be significant digital processing to encode and decode all the data that's coming and going. Then more data processing to turn massive data streams into both individual TV channels and a modem for the Internet: for the TV channels, some interface circuitry to generate HDMI; for the Internet, a router/WiFi port.

Does anyone still need baseband audio and composite video? Possibly, so we might as well add the decoder circuitry and a couple of op-amps for the analog audio and video.

(Source: Maxim Integrated)

(Source: Maxim Integrated)

Additional subsystems needed include an IR receiver for the TV remote and miscellaneous power supply support.

So, how shall we partition all of this? And how much can be squeezed onto one slab of silicon? Let us know your thoughts on the partitioning. Have you worked on any of the subsystems described here such as HDMI or laser drivers? What design problems did you deal with?

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35 comments on “Let’s Put a Set-Top Box on a Chip

  1. eafpres
    October 18, 2013

    @Brad–there has been a war going on for at least a decade to get control of that set top box.  Whoever wins there controls content into your house and stands a chance to make money on it.  Microsoft would like the X-box to be that box.  They have Netflix streaming now.  Google wants some of the action.  As does Apple.  And the cable guys.  And the telcos.  And the ISPs.

    With all these combatants it seems unlikely to settle on a SoC too soon.  So the partition probably has to have less function than you could do, just because nobody is 100% sure what they will do.

    It also matters whether what is coming in is internet or television.  In the television world you still have all the channels to deal with.

  2. Brad_Albing
    October 18, 2013

    @eafpres – good points. I was looking at it purely from an engineering point of view. But you're right – there are strong marketing issues that will affect this and go beyond what I think we can squeeze onto a piece of silicon.

  3. Netcrawl
    October 18, 2013

    @easpres @Brad its a new battle- to get control of the set box, this one is a “pure technology battle”, its a all about chips, cramming too many “smarts inside the chips”, who got the most processing power. Gaming is  a big business, and most of today's semiconductor companies are looking to game consoles market to fuel future growth. Growth primarily coming from SoC products fro both Sony and Microosft's next generation consoles.

    Companies want a piece of actions, from telcos to hardware players, Microsoft is a good example, they want their Xbox to be the center of today's living room.  

  4. Netcrawl
    October 18, 2013

    @Brad you're right its about putting everything inside the silicon, how far these companies can go, I still remembered the Sony-IBM partnership, the works on processor known as the cell chip- the brain of the Sony Playstation 3.  They crammed 9 processors onto a single chip, that's massive! they're pushing the boundary of limits, for graphics no other chips in the world can touch it at that time. Gaming is pushing the boundary of limits when it comer sto real-time graphics and much sophisticated and hihgly immersive user experience.



  5. samicksha
    October 19, 2013

    I do have set top box installed, co-axial cable getting terminated to it, although i dont have much problem with wire but box gets heated up very soon, i recently read about QAMi5107 Low-cost QAM demodulator and MPEG2 decoder SOC for set-top boxes, what makes me double check is price which plays important role for service providers defining a STB. What i understand is, by combining the function of the digital-signal demodulator with the MPEG decoder in a single package, it reduces the production costs.

  6. Scott Elder
    October 21, 2013

    I'd be happy if every content provider simply streamed their IP over the Internet and we just get rid of cable TV (i.e. set top box) altogether.  

  7. Brad_Albing
    October 21, 2013

    @Netcrawl – good point about the games – I hadn't even touched on that as part of this system. But I should have included I/O for gaming equipment.

  8. Brad_Albing
    October 21, 2013

    @Scott – I've been looking into that a lot recently – trying to see if I could just stream the 4 big networks and the lesser cable networks. Just grab what I wanted and ignore the rest. Assuming I can get an internet pipe with sufficient bandwidth – which I think I now have from my service provider – so now I just need to access the programming in some convenient manner. We'll see how that plays out.

  9. eafpres
    October 23, 2013

    The question is will the STB converge with the cable modem and cable decoder, and will that only be available over the cable pipe?  Consider my current situation.  I have Comcast digital cable but no DVR.  I use a Zoom cable modem to bring in internet and convert to WiFi.  So my internet and my cable are coming in the same physical coax.  But I have no easy way to run my TV with an internet service, becuase my TV is a basic flatscreen that can take RF/cable input.  And the simple Comcast box, not really even deserving of the “set top box” moniker, doesn't give me internet back to RF capability.  So I need at least another box or another TV or both.  My head is already starting to hurt.

    I'd love to get, say, Netflix streaming for $8/month and drop the much higher cable bill.  But as long as Comcast is my internet provider, they are in the mix one way or another.  Meanwhile, while their on-demand movies might be priced relatively high compared to a no-limit service like Netflix, what they do have is replays of network shows free via on-demand (as long as I've already paid the premium for on-demand service).  

    The bottom line here is that while there is competition for the “gateway”, there are lots of moves going on for content, which is ultimately what the consumer cares about.

  10. Brad_Albing
    October 23, 2013

    @eafpres – That's very close to my situation, except it's Time Warner.

  11. jkvasan
    October 25, 2013


    I have a philips TV 42″ LED with in-built set top box. I have a single remote for all operations. This is more convenient compared to an external set-top-box. Anyone is using this kind of a TV?

  12. eafpres
    October 25, 2013

    @JKV–so your cable operator supports the STB inside the TV?  In my market you have to get the box from the cable company.  I could buy the cable modem to WiFi myself, but the box for the TV must come from them. (Comcast).

  13. jkvasan
    October 25, 2013

    My cable operator has a deal with Philips. A good channel package was also given as a promo.

  14. Davidled
    October 25, 2013

    I would use Android or Linux Mini PC connecting to LED TV via HDMI port to get the movies and Google play games. Size is about USB. I get access internet. TV is controlled by wireless remote controller.

  15. WKetel
    October 26, 2013

    Streaming all of that TV garbage over the internet would be an absolutely HUGE waste of bandwidth. Let all the broadcast folks and the cable folks keep it in the air and in the cable. Wasting internet bandwidt on stuff that would be over the air or in the cable would be STUPID. Yes, it would be convenient for the few who waste all day with garbage, but there are much better things to do with the bandwidth that we have. The power burned in those data centers would be much more if everything were streamed ove the internet. So why use such an expensive transport medium sending out TV signals, no matter which kind, it is still TV. We really don't need that dumb a waste of bandwidth.

  16. Scott Elder
    October 26, 2013

    Cable TV set top boxes are the single largest consumer of power in the American home.  This makes sense when you consider that the box runs all day and night regardless of whether anyone is watching, there is on average 2 boxes for every home in the US alone, and these boxes do things that are no longer necessary (i.e. record on a DVR a show that could simply be stored in a single location in the cloud and accessible on demand).

    Conversely, a cable modem for the internet is less than 10W.  There is no need for more than one cable modem per house.

    My set top box gets very hot.  My cable modem is powered from a wall wart.  I wouldn't be surprised if set top boxes are history in 10 years.

  17. yalanand
    October 27, 2013

    An international semiconductor leader serving clients across the spectrum of electronics apps, has presented two set-top box System-on-Chip (SoC) families, codenamed 'Monaco' and 'Cannes', that include devices with Ultra HD resolution (2160p) and HEVC video-decoding support.

  18. WKetel
    October 27, 2013

    set top boxes get hot because they were all designed for minimum cost to produce. No consideration at all was given to efficiency, even in the current generation of boxes. Simply switching off everything that is not needed when it is not needed would reduce the heat a whole lot, although it would add a bit to the cost. And using a more efficient design and components would also reduce power consumption. What is needed there is a federal standard for maximum box power consumption.

    Of course your cable modem does not get very warmn or use very much power when not in use. That is because most of the functionality is located in your computers, which you may switch on only when you choose to use them.

    And at one time I did have an external switch to power-down my cable box. It was slightly less convenient but it did save electricity. And it broke no cable company rules, or any laws, it just reduced power consumption a bit.

    So it becomes a tradeoff sort of thing, wasting power with poorly designed cable set top boxes, or waste internet bandwidth duplicating what is alrady on the cable.

  19. jkvasan
    October 28, 2013


    That seems to be a good choice. However, bandwidth is important and also your internet operator must support streaming, I guess.

  20. Vishal Prajapati
    October 28, 2013

    @Scott, I also think that set top box will disappear in the short time. They will be integrated inside the TV itself. One of the product is live here in India is Videocon. 



    There is also a new standard DDB being adopted by lot of manufacturers which I think is futuristic.

  21. Brad_Albing
    October 28, 2013

    @eafpres – some TVs (not mine) have what is essentially a smartcard that handles whatever is needed in conjunction with the electronics in the TV to process all the digital channels. I'll see if I can collect more info and report back with another blog.

  22. Brad_Albing
    October 28, 2013

    @JK – agreed – you'd need an internet connection with lots of bandwidth.

  23. Brad_Albing
    October 28, 2013

    @WKetel – OK, well sure, if you want to discuss actual content, maybe it's not the best use of bandwidth. Except for Jerry Springer. And reruns of Lawrence Welk.

  24. Brad_Albing
    October 28, 2013

    @Scott – I wouldn't be surprised if set top boxes are history in 10 years . So why did I bother writing about them 🙁

    You do make a good point about the power draw, tho'.

  25. Brad_Albing
    October 28, 2013

    @Scott – re watching TV from the cloud – I'm seeing that now with HBO-On Demand et al. (that the one that I keep seeing promos for).

  26. Brad_Albing
    October 28, 2013

    @yalanand – I recommend that you blog about it. Email me an outline or a summary and I'll provide the soapbox for you.

  27. Brad_Albing
    October 28, 2013

    @WKetel – yep – there is that convenience factor. You don't have instant access; you have to go to that power switch and turn it on and wait for it to go thru its POST and handshake sequence….

  28. WKetel
    October 29, 2013

    BAlbing, Thanks for the offer of some useful information when you can get it. That would be quite interesting.

    But here is a question about your wondeful new television: how much power does it consume when it is “off”? Either an ammeter, a wattmeter, or some pther method just to see how “off” that off setting really is.

    An interesting project would be to take one of those old-technology outside wattmeters and wire it up with a cord and an outlet and use it to momitor the power consumption of single devices. I did that with a surplus unit a few years ago and it was educational.

  29. WKetel
    October 29, 2013

    With my previous television, which had a CRT, the cable box was always ready about the same time that the set was.  And our present set, a recent medium LED flatscreen model has to go through it's own boot up procedure each time that it is switched on, and that is from standby, not off. So it would not be  much of a change.

    And anybody who has such a short attention span that they can't deal with that gets no sympathy at all from me. They can pay an extra monyjly surcharge for energy wasting appliances.

    Actually, now that we have smart meters that can detect and report the draw moment by moment it should be a straightforward process to completely revise the utility rate structure. A higher rate for those loads that never switch off comes to mind. But that would be a subject for a different discussion, wouldn't it.

  30. Brad_Albing
    October 29, 2013

    @WKetel – you wouldn't think it would need much power just to keep its memory alive and remember all of its settings. But I bet it does use a bunch. I should check.

  31. Brad_Albing
    October 29, 2013

    @WKetel – yep, a different discussion – but a good and worthwhile one.

  32. WKetel
    October 29, 2013

    As a matter of fact I DID start another discussion. At least I think that I did. I clicked on the “start a board” option and posted a more complete version of that comment. I don't know what happens next. Where or how others see it. Don't know. Is it like writing on the wall? 

  33. jkvasan
    October 30, 2013


    My philips TV is a great device for viewing TV channels but is a pathetic device when it comes to even simple browsing. It is very slow and takes ages to open a web page. Remote pairing with my android works well but selecting and viewing youtube videos is a pain.

  34. Brad_Albing
    October 31, 2013

    @WKetel – It is like writing on a wall. I'll go find it and comment more.

  35. WKetel
    November 1, 2013

    After you find it, it would probably be worthwhile to provide a bit more information after a person clicks on “start a blog”. While I usually have enough time I don't always have enough time to drive a blog of my own.

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