SparkFun will be closed Nov 26th and 27th for the Thanksgiving holiday. Orders placed after 2:00pm MT on the 25th will ship out Monday the 30th.


Member Since: July 10, 2010

Country: United States

  • Don’t forget, you can supply a Vref to the arduino the change its analog read scale. Supply say a 500mV reference, and you’ve got ~350ish measurements in the 0 to 174mV range.

  • Good to have somebody touting safety. Even so, Mikkel J is actually correct. Each of the chargers he listed can be set to charge at the maximum rated current for these cells, which is 100 mA. The end user just needs to make sure it IS set to that current, and not higher.

  • The ratings are exactly what you would expect. The MOSFET can handle a max of 96W, or 50V, or 60A, not 50V and 60A. So it could do 50V and 1.92 A, or 1.6V and 60A. Anything less than or equal to 96W

  • Still not the same thing though. Pololu’s are 14.5mm total length, Sparkfun’s are 20mm. You can’t push Pololu’s through a one-sided copper perfboard and have it connect to a breadboard and have header connection on top of the board, even if you do adjust the plastic.

  • Hey I never got this issue solved. I’ve already posted a bug report on the github, to which none of the responses are yet helpful: https://github.com/damellis/attiny/issues/19

    I’m using the board definitions from Github, I’ve tried both the 32-bit and 64-bit USBTinyISP drivers (only the 64-bit seem to install properly), my IDE is 1.0.5, there’s no components connected whatsoever, the ATTiny85 is known to be working, the ATTiny is plugged in the right way, board selected is ATTiny85 1Mhz internal, programmer is USBTinyISP…I really don’t what else to do here. This board seems to have been a waste of money. Error is still initialization failed, rc=-1. Here’s a link to the full error. http://i306.photobucket.com/albums/nn255/Krb686/tiny_programmer_error.png Can you possibly help? If not, can I get a replacement? Cause if nothing works, then the board must be put together wrong, or the ATTiny84 on the board is bad. Also, the LED comes on orange in the bottom corner of the board if that means anything.

  • Interesting fact, solar irradiance maxes out at around 1366 watts per square meter, and this solar cell is 1 / 133,333 square meters, so that comes out to a solar input of 10.2mW of power on that tiny little diode, which causes it to put out 16.5uW of electrical power, so it has an efficiency of 1.6%.

    Pretty cool if we had much higher efficiency cells, getting that much power from that small of a space. Gotta love the sun!

  • I’m confused by how you set up your sensor. If you set it up so that alternate polarities rotate past a single side of the sensor it should work fine. Usually in tachometers, I would guess non latching types are used because a single fixed magnet can turn the sensor on as it passes and again with each successive pass rather than just once on the first. Earlier someone suggested resetting the sensor by switching the power and then delaying, which is clever for some uses, but would not work for a tachometer higher than 100 rpm, or faster than the minim reset time. Also for anyone else reading, don’t think about buying this for a levitator because it can’t be done, or maybe I just can’t figure out how to. An electromagnet would switch this on or off, and a floating magnet with reverse polarity approaching the reverse side of the sensor would cause no change. I should have thought about that before I purchased this

  • So I just bought this thing, got the IDE running, installed board definitions, plugged in the ATTiny85, now when I try to upload it gives: intialization failed, rc=-1 Double check connections and try again…

  • Come work for Sparkfun! All employees get a free livestock companion!

  • He meant to say “It would be cool and feasible to have it run off a nuclear reactor”.

No public wish lists :(