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Altera_Forum
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15 years ago

Help about the connection between IC of voltage 5V and cyclone II

Now I've got a cyclone II(3.3v in doc) device.But I've only got a 5V D-A IC.Can I connect them directly?especially output from 5V IC input foot of cyclone II(3.3V in document).I know the signal outpu...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

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But not sure if the signal from DA IC will damage the cyclone II

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Unfortunately, yes. I don't know, why you need a signal from DA converter to Cyclone II at all. Anyway, for a slow signal, a resistive divider is the most simple method. A 5 V tolerant logic gate suplied with 3.3V, e.g. 74LVC series can act as a level converter for fast signals.