I suppose the choise of power supply voltage also depends on what circuitry you
are tying the port pins to. If for some reason one needed a "safe" way to
interface to a 5v I2C chip, also consider the PCA9306 chip from TI.
----- Original Message -----
From: Geert Vancompernolle
To: [email protected]
Sent: Sunday, December 03, 2006 6:01 AM
Subject: [foxboard] Re: Output pins 5V tolerant: a question.
You're right, Wouter.
Should have noticed this myself, but apparently I didn't...
Maybe one of the reasons to stick to the +5V is that you might lower
the current of your total project.
BTW: you're living in Belgium too, isn't it?
At least, your name sounds "Belgian"...
Best rgds,
--Geert
--- In [email protected], "H_O_U_S_Y" <[EMAIL PROTECTED]> wrote:
>
> Me again,
>
> In the datasheet of PCF8574 I read:
>
> "Operating supply voltage 2.5 to 6 V"
>
> So why worry? Just power that chip with 3.3V and forget the 5V
> level ;)
>
> Regards,
>
> Wouter
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