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Honored ContributorVoltage GPIO DE1/DE2?
Hello! I have a question, everybody help me. How much is the voltage input/output GPIO DE1/DE2? And if i assign high signal (5v), low (0v) from power supply to GPIO, Kit DE1/DE2 have get signal with value is 5v (Logic 1) and 0v (Logic 0). Thanks
7 Replies
Altera_ForumThe voltage of GPIO will depend on the IO standard that you set to it. You can double check the expected voltage levels from datasheet of the device.
- Altera_Forum
5V is too much for both DE1 & DE2 kits - it'll work for a short while before you damage it.
3.3V maximum. Cheers, Alex - Altera_Forum
Thank for reply my question! But i'm doing a project transmit audio with UART, recieve singal from UART is 5v (Logic 1), if i use variable resistors to convert 5v -> 3.3v, it may wrong?
- Altera_Forum
The DB9 serial port on some of the DE series boards are connected to a driver chip that can handle 5 volts easily. Alex was referring to the pins on the FPGA itself. You can easily damage an FPGA with too high a voltage.
- Altera_Forum--- Quote Start --- The DB9 serial port on some of the DE series boards are connected to a driver chip that can handle 5 volts easily. Alex was referring to the pins on the FPGA itself. You can easily damage an FPGA with too high a voltage. --- Quote End --- Thanks you! 1. But UART were designed by me. it just recieve singal from GPIO, i can assign signal RX to DB9 serial on DE? 2. If on wire RX signal use schematic 5v -> 3.3v and provide to GPIO, it true? it look like image. http://www.alteraforum.com/forum/attachment.php?attachmentid=11527&stc=1
- Altera_Forum
You might need to add another chip to step down from 5V to 3.3V to work with the FPGA.
- Altera_Forum
Your circuit, to drop your 5V signal to 3.3V, should work just fine.
Cheers, Alex
