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March 29, 2009
about 3 years ago
Just got a few blue and yellow of these to test out. Haven’t done much other than bread board them to make sure everything lights up. In my setup I drove a particular segment (e.g. segment a or b) on all four digits simultaneously, then I would check segment b, c, d, etc. My multimeter gave me 2.35 mA draw for four leds (total, not each) using a 1 kOhm resistor. For any indoor application, the blue is easily visible only drawing 0.5 mA per segment continuous (5 V, 4.7 kOhm test resistor driving one segment). The yellow units are not as bright and draw more current (0.68 mA, 5 V, 4.7 kOhm), but I think the amber/gold color looks really good.
Edit: The yellow can be bright, but take more current. According to the datasheet specs blue @ Vf=3V, Ic=20mA, the yellow @ Vf=1.9V, Ic=30mA. But blue has twice the luminosity of yellow at half the current. They are both plenty bright enough though.
about 4 years ago
Does anyone know if this can be used as a general JTAG programming cable for other devices like CPLDs or FPGAs? Note I’m only asking about programming, I don’t need the emulator/debugger features to work for other devices. If not, are there any that can?
about 5 years ago
Are these momentary switches? And by the diagram I’m guessing they are normally open? Did I just answer my own questions?
News - Happy Free Day
about 5 years ago
On the upside I now have two wish lists full of things I would like to have, since I perused nearly every product on the site in anticipation… the voice command recognition stuff looks interesting…
replying to my own post here… but I’m not complaining. I think it’s awesome that Sparkfun does this, but the first time my alarm failed on me and it ended before I woke up. This second time, I managed to get $10 bucks (I’ve been visiting since late ‘07/early '08), shocked me to learn I didn’t buy anything til '09). I would have liked the chance to go for the full $100, but when it takes 15 minutes to get the home page to load I thought it better to go the other route.
I’ve had the disappointing experience of preparing for both free day’s and missing out on both.
No public wish lists :(
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