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Altera_Forum
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15 years ago

Cyclone III with 5v inputs

I'm trying to connect approximately (16) 5v TTL inputs into a Cyclone III eval board, the terasic de0 [1]. These are all input towards the FPGA only. The eval board has (2) 40-pin IDC headers for t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

The TI 74CBTD3384C

http://www.ti.com/lit/ds/symlink/sn74cbtd3384c.pdf

buffers used on the MAX II PCI development kit are bus-switches with the diode internal to the device. You can power them from 5V and they'll clamp bidirectional signals to 3.3V levels.

I've used a bunch a bus switches on lots of designs, but never realized they had parts with the diodes internal to the devices.

Cheers,

Dave