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Member Since: February 3, 2009

Country: United States

  • Using it with a solar project. It works but the breakout is REALLY BAD DESIGN, imho. The problem is that the board leaks ~1mA through idiotic pull-ups (POL and others). It should not be surprising that this is used in context with very limited power supply. which makes the sloppy design even more embarrassing for Sparkfun. Please please update this!

    The data sheet indicates that pullups are required for proper operation of the LTC4150 and the 3.3K resistors chosen are larger than the minimum required. Unfortunately we cant build a board that works for every customers unique situation but we to try to provide you with information that allows you to tailor a board to your requirements.

    I would suggest swapping R5,R7 and R9 out for larger value resistors to get a lower current drain. 10K’s should work but you might try higher. Alternatively, you could remove those resistors altogether and use internal pullups on your μC if it has that feature.

    If you find a value that works well, let us know. We may incorporate that into a future revision.

  • 3.3 volts on the CTRL pin is definitely enough to cause the relay to trigger. 3.3 volts on the 5V may not be enough to reliably power the coil in the relay though since it’s expecting 5 volts. I tested an older version of this product on 3.3 volts and it worked fine, but since it’s below spec, you may run into trouble. Give it a shot with 3.3 volts and if you’re having trouble, bump the voltage on the 5V pin up to 5 volts and you should be good.

  • Hi Jordan. It’s not really intuitive on this board, but the terminals labeled R are for the center taps and W and B are for the outside legs. Try putting your center tap wires on R and see if the problems clear up. The reasoning behind this color scheme is it matches our load sensor. Your sensors might have different colored wires though.

  • The data sheet mentions that chlorinated solvents will attack the material the sensor is made of. The minuscule amount of chlorine you find in pool water should not be an issue though. I have not tested this sensor so I can’t comment on daylight skewing the readings. It would probably be a good idea to keep this out of sunlight to ensure proper operation.

  • Thanks for asking! The Arduino bootloader is already on the board so you can upload your own firmware if you want to. Just use board type “Arduino Pro or Pro Mini, ATmega328 (3.3V, 8 MHZ)“ in the IDE.

    One warning though. We don’t have an .INO sketch of the original firmware so if you reprogram the board, you can’t go back to the original firmware without using a hardware programmer.

  • What meljr says, plus better isolation between the high voltage and low voltage sides of the board and this version uses thicker traces (more copper) to increase the current carrying capability.

  • Is it Atmega32U4 pin PB3 you’re looking for? Arduino calls that pin 11, but on our board we’ve redefined it to pin 14 in software. Anywhere you would normally call pin 11, just rename it to pin 14 and you should be OK. If you’re using SPI, it’s MISO either way. I don’t recall at the moment why we renamed that pin, but we did have a good reason for it.

  • We sell them here! :-)

  • ——————– Tech Support Tips/Troubleshooting/Common Issues ——————–

    If you ever need to reload the original Blynk firmware to your board:

    • Download the this file from Github that contains the core firmware plus the Blynk board Eagle files.

    • Unzip that file, and in Arduino, navigate to the BlynkBoard_Core_Firmware folder in the file you unzipped.

    • Open the BlynkBoard_Core_Firmware.ino file in Arduino. You should see several other tabs open besides the main sketch.

    • Click upload and you should be good to go!

    Note: It takes a long time to compile. This was tested in Arduino 1.6.6.

  • Nope, that’s intentional. Check the Assembly Tips section of the hookup guide for more information on why we designed the board this way.

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