How to Make a Wireless Sensor Live for a Year on One Tiny Coin Cell Battery
I&#x27;m actually building a product that incorporates a CC1350 in it, which is the variant that has both a 2.4 GHz and a proprietary sub-1GHz radio.<p>These chips are totally amazing.  TI used every trick in the book to help the designers save power.  There&#x27;s even a specialized coprocessor that uses special low leakage silicon to handle some simple 16 bit I&#x2F;O processing so you don&#x27;t have to wake up the main processor, and the main Cortex-M3 is pretty darn low power already.<p>I am kind of annoyed that you have to call into their ROM routines to use the radio, though.  The datasheet is a snarky little tease that says ha ha, the radio registers are somewhere around these addresses but we aren&#x27;t going to tell you what they do!  Shhhh it&#x27;s a secret!  This is particularly annoying because I could make my life a lot simpler if I could interface with the Nordic shockburst protocols, and TI&#x27;s firmware only knows how to speak TI simplelink packet formats.<p>The thing that TI isn&#x27;t talking about is that they did some stuff around the voltage regulation that looks like they were planning on pushing some kind of energy harvesting companion silicon.  It&#x27;s just a guess, but they might announce something in the future along those lines.  Whoever ends up first to market with a productized energy harvesting IoT chip is going to print bucketloads of money.<p>There&#x27;s also a lot of stuff going on in the low power LTE space right now.  Altair semi announced the 1250 chip, which is -- get this -- power competitive with the TI chip for low frequency telemetry applications.  AT&amp;T and Verizon have already launched their cat-M1 networks and cat-NB1 is going to be out by the beginning of next year.  Those protocols use oversampling and a bunch of other mad scientist RF hacks to get even more range than the LTE radio in your phone.  The bandwidth is really low, like modem or ISDN low, but there&#x27;s a ton of applications that can be implemented with literally one bit per day worth of data.  The chips are getting pumped out in volume now, and the cost regime is actually causing revenue jitters at the carriers.  They want to squeeze some extra revenue out of LTE IoT space since it&#x27;s basically free for them to implement since the LTE IoT designers figured out how to reuse the otherwise useless guard bands surrounding the real full-fat LTE signals your phone uses.<p>However, it&#x27;s kind of a tough problem to figure out a cost model where customers are paying something like $10 a year for maybe hundreds of devices that are so cheap that the most expensive item on the board is the SIM card.  And even that&#x27;s going away in the 2nd generation IoT chips now that someone figured out how to get around the UICC requirement for provisioning by doing something funny with a protected element in the main LTE radio.<p>Also check out my profile.  It&#x27;s not a joke, someone made a homebrew monitoring solution out of someone else&#x27;s IoT chip to keep track of cow farts because they wanted to adjust the feed based on farts per minute or something, I didn&#x27;t really understand it.