Have Quad Relay Issues - start here!

Robotics
1

Dear Quad Relay Owners and Users,

After a round of troubleshooting I have identified the source of the most common issues with the SparkFun Qwiic Quad Relay, so if you are experiencing one of the two following issues read on.

  1. The power LED shuts off one day and never comes back on.
  2. The board stops responding to I2C commands.

Explanation of the first issue:

It turns out a specific diode needed for “clamping” voltage is under-rated for the power circuit it’s on when running at 12V. As a result, running the quad relay using a 12V wall wart will inevitably cause the product to fail.

Solution:

The solution going forward for the product is simply a higher rated diode. However, as a user (assuming you don’t have a library of schottky diodes in your office) is to close the “BYP” jumper on the underside of the product and power with a 5V wall wart. Our Hardware Overview has pictures on where it’s located. If you do have a schottky diode rated for at least 15V peak reverse voltage and 1A forward current, you can replace diode “D6” yourself (Link to schematic).

Explanation of the second issue:

Some boards have stopped answering I2C. Actually, I have not figured this one out. I’ve broken a number of boards (at least 8) trying to recreate this issue, including frying regulators.
I believe that locking the memory from being reprogrammed may be a solution, that this may keep the onboard IC from getting wiped. If I find out more than I’ll post an update here.

Solution:

If your product is not responding, it can be re-programmed with the firmware in the repository, assuming that your savvy enough to connect to the six programming test points on the underside of the product. If you are and you want to go through the hassle, then you can get the design files from the Hardware Repository to orient your programmer correctly.
I confirmed that I could fix the one Quad Relay that I had received, that was borked in this way. Otherwise, you can file a return with SparkFun.

Note from Engineer

I’m sorry for the trouble. When this product came out we didn’t have near the level of review processes that we have in place now. Something like an out-of-spec diode would not even make it onto a prototype these days. If you have any questions please post them below.

Elias Santistevan

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