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Info in a differently-badged version of this product - Aiptek PenCam I picked up this neat gadget at a computer fair recently. It can be used as a PC-attatched camera for webcam type usage, and also a standalone digital camera. Its basic resolution is 352x288 (CIF), and can also capture at 178x144 (QCIF). It can hold 20 CIF images in internal memory. No image compression is used, which results in a fast capture rate - the device can capture 20 images in about 3 seconds. I'm sure the innards of this device could be adapted to some interesting alternative uses, like putting it on a model aircraft, balloon or rocket for aerial photography. Another possible idea - it should be possible to squeeze the board with some button cells into a large car-alarm keyfob case to make a neat unobtrusive 'spy camera'. How about an automatic 'doorbell-cam' that takes a picture of everyone who rings the bell... or hook it up to a PIR motion detector... By removing the case, LCD, sounder and switches, the weight is only about 10 grams. Power consumption is rather high, however - 67mA at 3V, dropping to 40mA at 4V (It rises again as the voltage increases above 4V). This power draw indicates that the image sansor is powered up continuously, presumably so that its auto-exposure will be operating, and ready to take a picture immediately the button is pressed. With this level of power draw, lithium coin cells are not a viable power source, however three LR44 alkaline button cells should give enough life for short-term uses like model aircraft, where weight is critical. (If you look around, LR44's can be bought for well under £0.10 / US$0.15). Although alkaline button cells give 1.5v each, I'd suggest using 3 instead of 2 to reduce current draw - at these current levels the cells will not give 1.5v each for long, and current draw will rise rapidly as the battery voltage falls, possibly wiping the stored images. For longer life use in weight-critical applications, 3 volt lithium camera batteries like the CR2 should work well. Three small ni-cad button-cells should also be suitable. Power must be maintained to hold the images in memory - one thing to be aware of is that the device draws 0.5mA even in 'off' mode (to refresh the SDRAM image data), which will be an issue if using small cells. The unit switches itself off after 30 seconds.
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