Member #444741

Member Since: June 7, 2013

Country: United States

  • It occurs to me that if there were any floating pins going into, say, interrupts, that 1msec is a plausible timeconstant for charging of a pin's capacitance by PCB leakage current: 10pf / 10nA = 1msec/v. Maybe it would be informative to define all unused pins as outputs, in the setup section of the program, and run it again...

  • answered my own question... The datasheet shows a filter in fig42 with 33uH & 1uF on each output lead. Optional of course. Sheet says it may improve battery life a bit. By less than factor of 2 I guess.

  • It seems to me a series inductor then a shunt capacitor right near the PCB could suppress that RF interference. Could anybody suggest particular values? Is 10uH & 1uF enough?

  • I suspect this unit scans from short delay/distance to longer, looking for correlations. It looks like it stops and reports the distance as soon as it decides it had found a correlation, but it won't keep scanning after that. Maybe it could scan for multiples if reprogrammed internally; maybe with the mfr eval board? Then there would be fuzzy limits between smeared and distinct responses...

  • I think water is a pretty difficult target. It has lower index-of-refraction than most other things, so it reflects less than half of what a window reflects. The new datasheet says 'no washing, it's not sealed' for the soldering process , so I think living full-time inside a fluid tank is highly unguaranteed. Spending power to keep it always 5-10c warmer than the environment might help.

  • I think a clear fluid in a white or metallic container would have serious difficulties. Making the container black would help, and having a fluid that was dark or densely pigmented would help too. So I doubt this works great for water or gas-tanks. Measuring distance to a white float would be needed.

No public wish lists :(