Thread: Digital to OI Analog
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Unread 27-01-2007, 03:10
marcan marcan is offline
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Re: Digital to OI Analog
I just tested my OI to 100mA from Port 1 Aux (pins 1 and 4) running two (overloaded) white LEDs. Multimeter measures 100mA, voltmeter measures 4.5V. Okay, so the voltage does drop a bit, but I intend to run 3.3V circuitry using a switching buck regulator anyway, and 4.5V will still work fine for most 5V ICs too. My calculations say worst-case the aux circuits will draw 100mA at 3.3V, which is 66mA at 4.5V and 60mA at 5V (remember, this is a switching regulator, not a linear one, so it ideally does not waste any power). Even with some extra stuff thrown in (LEDs, DC-DC inefficiency, etc), I still have room.