New idea for 5V - 3.3V translation

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
Post Reply
Phobbes
Posts: 1
Joined: Mon Apr 21, 2008 8:57 pm
Location: New York, NY

New idea for 5V - 3.3V translation

Post by Phobbes » Tue Apr 22, 2008 3:36 am

I don't have any fast enough zeners on hand, and it seems like a suboptimal solution anyways, so I tried this out: I used a standard 4050 CMOS buffer powered with a adjustable regulator at 3.3V.

It doesn't seem to be recognized by the host computer, though. I used a signal generator to run a 1.5MHz 0-5V square wave into it and the output was a pretty clean 0-3.3V square wave, but delayed by about 60ns. Do you think this is too much delay for proper communication? Am I doing something else that's dumb?

Image

Post Reply