Problem with a MC68HC908AP16

[JrCL]

Good day, I have a problem with a MC68HC908AP16, when I work him at 3v it doesn't begin, the pin RTS stays in under, if I work him at 5v it works well that I can make so that it works me at 3v. 
 
Thank you

[bigmac]

Hello, and welcome to the forum.

The 908AP16 is unsuitable for operation from 3.3 volts.  The Vdd voltage range specified in the datasheet is 4.5-5.5 volts.

As the supply voltage increases, the LVI module will remain in the reset condition until the Vdd rises above typically 3.45 volts (3.65 volts maximum threshold).  But the normal operating voltage should not be less than 4.5 volts.

Regards,

Mac

[Klined]

The 908AP16 functional operating range is specified as being 2.7-5.5V in its datasheet.  The 908AP16A is specified to run @ 4.5-5.5V.

K