Answers Database

Are 9500 Inputs 5 volt tollerant when Vccio is 3.3 volts?


Record #2139

Product Family:  Hardware

Product Line:  9500

Problem Title:
Are 9500 Inputs 5 volt tollerant when Vccio is 3.3 volts?


Problem Description:
Keywords: 9500, Vccio, 5, 3.3, volt, inputs

Urgency: standard

General Description:

Are 9500 Inputs 5 volt tollerant when Vccio is 3.3 volts?


Solution 1:

Yes, 9500 Inputs are 5 volt tollerant when Vccio is 3.3 volts.

The voltage level of Vccint is applied to the internal logic of
a 9500 CPLD.

Vccint should be between 4.75V and 5.25V for comercial devices and between 4.5V
and 5.5V for industrial grade devices.

The input clamping Diodes of the 9500 CPLDs are controlled or
connected to Vccint.  Therefore, any input voltage between 2.0V
and (Vccint + 0.5V) can be used to represent a logic high input
voltage. This is independent of Vccio.

The voltage level of Vccio may be either 5V or 3.3V Vccio
controls the output voltage level.

If Vccio is 5V, VOH will be aproximately 4V
If Vccio is 3.3V, VOH will be aproximately 3.3V



End of Record #2139