Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
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

--- Quote Start ---

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.

--- Quote End ---

Thank you~~

Sorry....It's just a mistake(spell error)~~actually it's a ADC IC(TLC2543 --maybe an old device~~~but I've only got this in my lab).I can send the control signal to the IC,but not sure whether the data can transmit from IC to FPGA successfully.Ever I thought the method of using resistive divider too,but I'm afraid it will take additional unexpected puzzle.for 74LVC I'm not sure if the speed will be appropriate.I've just searched 74lvc157ADC to have a try.If it doesn't work,I think I'll buy a new A-D device........