• Try again

    Will Whang08/02/2017 at 02:19 0 comments

    So... it's almost a year for this project.
    Quite a lot happened this year, LoRa community has grown pretty fast,
    even SX1301 datasheet is now open without NDA.

    I'm still not able to make the first board working though, after re-soldering and testing, again and again, so I stopped for a while.

    I think I might overheat the chip though.
    I've checked the SCH with datasheet, no such big difference found.

    So I'll try again with version 2, designed for Raspberry Zero
    Added step-down for 1.8V supply, GPS module, 
    but removed RADIO_A because of the board space and layout reason.
    Also ordered new SX1301, maybe also a Concentrator from others to compare.

    Hope this works.

  • Some thought

    Will Whang08/29/2016 at 14:45 0 comments

    I always wanna REAL LoRa muti channel receiver, so after Googling I found that SX1301 is a chip

    specifically for this purpose, has a maximum 8 channel

    Although there is some concentrator board on the market, like mCARD or WiMOD iC880A

    but they are all for 815Mhz and 915Mhz ISM band, and I want 433Mhz

    So I need to build one ,but Semtech seems to be controlling SX1301 source

    luckily I found some SX1301 selling in China, so starting the layout.

    Microchip provide a very good detail about the schematic (LoRa® Technology Gateway User’s Guide), so for SX1301 section, the layout is just copy paste, since I have no idea what is going on there.

    for RF frontend, schematic is from SX1255 datasheet, I didn't combine the TX/RX and channel A/B for simplicity.