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  1. Like
    Adnan reacted to abecedarian in Best LP for WSN   
    If you want built-in LCD, you only have two choices: FR4133 and FR6989. Your 64KB limit narrows things down to FR6989.
  2. Like
    Adnan reacted to spirilis in EXP5969 supply voltage   
    hmm, maybe I was wrong then.  I do know the F5529LP is 3.3V perhaps the others are... don't have any with me to check atm.
  3. Like
    Adnan got a reaction from tripwire in EXP5969 supply voltage   
    Yes, it's accurate ans also I checked more than one kit, all of the produce the same Vcc (3.62) and at the same time I measured the voltage on exp5529 it gives 3.3 V.
  4. Like
    Adnan reacted to Fmilburn in EXP5969 supply voltage   
    VCC is 3.6V measured on my sample as well. The schematic on Page 39 of the LaunchPad Development Kit User's Guide (SLAU535B) shows power coming from a TLV70036DSEwhich is a 3.6V LDO.  So the pin maps or any other documentation showing 3.3V are incorrect.
  5. Like
    Adnan reacted to spirilis in EXP5969 supply voltage   
    that is weird, I am pretty sure I noticed 3.3V on mine last time I checked.  Your voltmeter accurate?
  6. Like
    Adnan reacted to jpnorair in Energy harvesting   
    Boost is easier.  At night the panel will be low-voltage.  At dawn it will increase voltage.  If you use a low-voltage solar cell, then you can keep the entire voltage range in the boost regime.  This is easier than buck-boost and more efficient.
    I designed a WSN device using a 1.9V solar cell.  In maximum California-summer sunlight it was 1.8V.  Indoors next to a window it was between 0.4-1.0V depending on the time of day.  With office lighting, it was between 0.2-0.8V.  The point here is that the whole voltage range will be observed during the operation of the device.
  7. Like
    Adnan reacted to Lgbeno in Energy harvesting   
    I cringe to see all of those resistors...
    Just remember that BQ25504 and TPS61097 are not functionally the same.
    TPS61097 isn't going to do MPPT on a solar panel although maybe one additional resistor to limit the charging current into the super cap would be all that you need. This also assumes that you have a panel that has Open voltage of a few 100mV less than 2.7.
    Sent from my iPhone using Tapatalk
  8. Like
    Adnan reacted to Lgbeno in Energy harvesting   
    BQ25504 looks like your ticket then. Taiyo Yuden has some decent super caps.
    Sent from my iPhone using Tapatalk
  9. Like
    Adnan reacted to Lgbeno in Energy harvesting   
    Cheap regulators often have high quiescent current so I would look into that.  Also in solar, some special consideration needs to be given for the MPPT of the solar panel because the panel will stop producing power if it's voltage is pulled too low.  By far the cheapest way to do this is with the $1 solar light and the boost converter method.  
    The ASIC inside the solar light handles the MPPT and NiMh charging, then the boost gives your circuit the right voltage.  SuperCaps don't really store as much energy as batteries and they are more expensive.  They are arguably more reliable for larger pulses of current but I don't think that it matters in this case.  You can boost to whatever voltage you like based on part selection as well.
    I started using NCP1400 for cost but I think the TPS61097A-33 is lower power.  Regardless, I figure I can get about 1 year out of a single AA battery so I think that is good enough.
  10. Like
    Adnan got a reaction from Rickta59 in Energy harvesting   
    Launchpads and RF components are provided with internal voltage regulator, that is the reason why these components can be supplied with a wide range of input voltages (2 - 3.6 V). So, I want to run the system on 2.7V (typical voltage of supercapacitor).
    On ebay I found many cheap regulators ($2 - $5) that can be used to adapt the output of solar panel to the supercapacitor voltage. I'm hesitated about using these products because I'm no sure about the reliability of these products.
    Another problem I expect to encounter is how to tackle the problem of voltage drop of supercapacitor below 2V which may be occurred rarely.
    The motivation of using a cheap energy harvesting circuit  is to reduce the cost of the whole system.
  11. Like
    Adnan reacted to chicken in Energy harvesting   
    TI has the MSP430 Solar Energy Harvesting kit:
    It's on the pricey side, but the documentation including schematics might be useful even when not buying the kit:
  12. Like
    Adnan reacted to Antscran in Energy harvesting   
    Hi Adnan,
    I have made a few energy harvesting circuits now and usually use Linear Technology IC's, they offer a good range of options.  TI also do a range of devices as well as do other manufacturers, but I am less familiar with these.
    You need to use a boost or similar topology (Sepic) if you want to have the system running when the solar cell is below the loads running voltage.  Unsure of the power output of your solar cell, but this will determine the charging speed of your supercapacitor at any given irradiance level and load requirements.  I have not used the voltage range that you require, but the LTC3105 should fit your requirements.  The circuit calculations are easy enough and the datasheet walks you through everything you need.
    Hope this is of some use,
  13. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    I think that the only path forward is to get started  You'll find out quickly what needs to be optimized and what is "good enough"
  14. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    MSP430FR5969 also has AES so that brings you to the difference between cc1200 and cc1120 is 2dB of Tx power.  If I were you I would do CC1200 and push the limits on range as far as possible with that extra 2dB.
  15. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    A quick glance shows that the two major differences are that CC1200 adds an AES-128 Accelerator and has 2dB extra Tx power.
    If you don't care about cost, just do CC1200 it is a superset of CC1120 and you can always pair down your code to move to CC1120.
  16. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    You're lucky.
    Buy all of these:
    and if you want to do cc1200, add this:
    Each node will cost you $95
    You can use Energia with this setup but it is not plug and play by any means, you'll have to do a lot of work with writing libraries for the radio and your WSN.
    EnergyTrace should be possible BUT I think that you need to use Code Composer Studio for this feature, someone who has tried it out can correct me if I am wrong.
  17. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    Doesn't really matter, you'll just need to think about how much money that you want to spend and how that you will construct your test setup.
    These radios are geared toward this kit http://www.digikey.com/product-detail/en/CC1200DK/296-36405-ND/4271561
    The kit comes with CC1200 modules and you can buy the cc1120 modules for another $99
    With these kits it will be difficultto use anything besides the built in MSP430F5438A.
    Alternatively http://www.digikey.com/catalog/en/partgroup/cc1200-evaluation-module-kit-420-470mhz/40641 has pin headers that you can wire to whatever you want.
    To kinda put it bluntly, none of the options are ideal because to develop and test sensor networks you need a lot of nodes and if each node costs you $50 or $150, thats a severe limitation.
    Thats why I built my own cheap nodes http://forum.43oh.com/index.php?/topic/8750-New-MSP430-Wireless-Sensor-Node
    Its hard to have your cake and eat it too
    Sent from my iPhone using Tapatalk
  18. Like
    Adnan reacted to jpnorair in Implementing WSN   
    I would use the MSP432 launchpad, because it has the best performance, the best low-power, and I am very familiar with ARM.
    If you do not have experience with ARM, the 5529 launchpad will be the best choice.  This chip has much better support than the FRAM ones have, and it can run basically twice as fast.  Since you're building only a pilot project (you're buying launchpads), quibbling over 1.5uA is just plain dumb.  Increase the size of the battery a tiny bit, instead.
  19. Like
    Adnan reacted to jpnorair in Implementing WSN   
    A typical duty cycle for a WSN endpoint is between 0.1% and 1%.  Yes, it can be lower if you are doing only transmissions at scheduled intervals, but this is not very functional.  I don't know if you are using someone else's protocol stack or if you are building your own, but I know all the major stacks, and all are at least 0.1% duty cycle.
    Even in the 10 minute beacon case, if you are using low data rate to get long range, you will use more power in TX than sleep.  "Back of the envelope" I calculated 4uA average current, which is more than the sleep current.  The MSP432 can sleep at 1uA, the 5529 at 2uA, and the 5969 at something like 0.5uA.  Really, this is a "drop in the bucket."  I've been designing WSN for almost 10 years now.
  20. Like
    Adnan reacted to spirilis in enrgy efficient launchpad   
    If your memory requirements are important as stated above, the FR5969 launchpad should work great.
  21. Like
    Adnan reacted to spirilis in enrgy efficient launchpad   
    The FR5969 and the new FR6989 launchpads would fit the bill nicely IMO.
    edit: Both only have 2KB SRAM though, however you can rework things to use the FRAM in place of SRAM if you need to (and can take the minor performance hit).
    Otherwise if having 4+KB of true SRAM is critical, the F5529 launchpad would fit the bill.
  22. Like
    Adnan reacted to jpnorair in Implementing WSN   
    There is a pretty big difference.  Read the datasheets more thoroughly.
    The biggest areas of importance:
    - CC1200 is good for narrowband, wideband, and spread spectrum.  CC1120 only narrowband.
    - CC1200 has FEC features.
    - CC1200 has lower power "sniff" feature.
    - CC1310 is designed to be easy to migrate-to from CC1200.
  23. Like
    Adnan reacted to roadrunner84 in Implementing WSN   
    You can use <insert favourite IDE> combined with the gnu compiler that is underlying to Energia, it's just a bit more work.
  24. Like
    Adnan reacted to Lgbeno in Implementing WSN   
    I'm pretty sure that there is little to no overlap between CC1120 and CC1101.
    CC430 has the same radio core as CC1101 afaik
    Sent from my iPhone using Tapatalk
  25. Like
    Adnan reacted to roadrunner84 in Implementing WSN   
    Energia is a terrible framework if you want to do serious low power work, just use CCS and plain C code instead of the Sketch framework.
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