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Product BOB-10901 | about 6 months ago

According to the datasheet, at 200mA LED output, the proximity is given at about 18,000 counts for 4mm and 40,000 counts for 2mm. It’s logarithmic, and because I’m too lazy right now to check, the linear resolution would be 2mm / (22,000 counts) = 0.0001mm / count which seems very very absurd: if you moved the reflecting surface the thickness of a human hair, it would change by 825 counts.

Product COM-10444 | about 10 months ago

The built-in PWM is a very nice feature, but the requirement for 6 resistors for one RGB LED to attain constant-current operation is a bit overkill.
Since I multiplex PWM on the microcontroller (using “bit modulation” to relieve much of the computing overhead), I prefer the PCA9922 which is a shift-register-style 8-channel constant-current LED driver with one resistor to set the current on all channels from 15mA to 60mA. It also supports a separate power supply for analog (the LEDs) and digital.
I designed a board that seems to work okay that puts two chips on opposite sides of a dual-sided board to drive 5 RGB LED’s (15 channels) plus a spare, optional LED for debugging, etc.

Product COM-10866 | about 10 months ago

Like a SMD version of Dr. Theopolis ( http://en.wikipedia.org/wiki/Dr._Theopolis ) …

Product DEV-10549 | about a year ago

Barring scanning the source code, what happens if you take more than 1000 pictures?

Product COM-09264 | about a year ago

Any common anode varieties? I find common-cathode is a hassle to work unless you’re hooking straight to 5V logic pins — it’s way easier to work with the common cathode NPN / common drain N-FET outputs on shift registers like http://www.sparkfun.com/products/734 , “Shift Register 8-Bit High-Power – TPIC6B595”.

Product COM-10312 | about a year ago

For what it’s worth, the data sheet specifies 1.8A maximum current which works out to just shy of 20mA * 32 LED’s * ( 1 red + 1 green + 1 blue ).

News - A Preview of the Quiz | about a year ago

So is there a “side bet” again this year?

Product COM-08203 | about a year ago

I never found another source for these, and presumably you won’t be buying more. Although it was lunch time when I stopped in a couple months ago, a few of you did get to see the super-bright LED ring. I’ll probably make an Instructable out of that project and I’ll be pointing people here to buy the parts, so you may want to make sure you can get more if nothing else (alternative: reveal your secret source!)

News - Meet Customer Service | about 2 years ago

Hey Paul,
Thanks for the tour on September 10 — fun stuff! Too bad nearly everyone was at lunch, and that the pick-and-place machine wasn’t running. But aside from that, it was nice to have friendly folks accommodating a stray Burner.

Product PRT-08818 | about 2 years ago

For comparison, the 20mAH cell ( http://www.sparkfun.com/commerce/product_info.php?products_id=9142 ) is 2.1 grams or 0.9g if you remove the JST cable and connector.