Pulled it out of a CD box set? What was it doing in there? Are you sure it isn't a store security tag? If you pass it through a pair of plastic monoliths does an alarm go off?
It was a fairly swank cd box set. :) I should have mentioned this, but the battery pack is four AA's. That's _crazily_ overpowered for an antitheft device; I think most of them are unpowered signal reflectors or rfid devices.
There's no capacitor, and the LEDs are in a pattern, so it can't be a 555 timer. The diodes are weird. One would be used for circuit protection, so that if the power was hooked up backwards, it wouldn't fry the chip. But two? Is the board single or double sided? It looks like it's double sided. Do you have pics of that side too?
Two diodes like that might be used to step down the voltage for the chip. There's a drop of .7V across each diode, so you could supply 3.6V to the chip, which is within the range of many kinds of microcontrollers (3.3V). Also, there's a pair of pads on the upper right marked I and 0. I dunno if that's an option, or if it's a programming pad. They look like they could be connected to "turn something on" in the chip.
Agh, I forgot to mention this? I forgot to mention this -- it's definitely a single sided board, what you see in those pictures is all there is. Also, I should note that the battery pack is four AAs. I'm assuming it's some kind of UC at this point, but we may never know what kind.
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Two diodes like that might be used to step down the voltage for the chip. There's a drop of .7V across each diode, so you could supply 3.6V to the chip, which is within the range of many kinds of microcontrollers (3.3V). Also, there's a pair of pads on the upper right marked I and 0. I dunno if that's an option, or if it's a programming pad. They look like they could be connected to "turn something on" in the chip.
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