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Old 03-27-2008, 10:42 PM   #13
dupa2
Constant Bitrate
 
Join Date: Jun 2006
Location: Chicago, IL
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wow, I'm surprised you ended up using such a weird solution for power button driver. First of all, the power button will accept standard ACPI signal, and since you work with 5VDC already, all you need is just one tiny transistor with pull-up resistor that will make ~0.5ms 0V pulse.

Instead of regular relays, I'd use solid state relays that typically can handle at least 10Amps, you don't need any high-end SSR, just get the cheapest one with triac output.

Your avr may die if you use relays directly, either from overcurrent on IO line or voltage peak from coil transient.

Since you use avr, you can actually implement your battery voltage monitoring (avr has ADC inputs), I think it could be cool feature.

Look also for AVR Butterfly, it's a cheap development board with LDC display and atmega169, it would simplify whole project a lot.
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