Answers Database

XC4000XL: VTT connections on 4000XL pinouts...


Record #1942

Problem Title:
XC4000XL: VTT connections on 4000XL pinouts...


Problem Description:
Keywords: vtt, pinout, xl

Urgency: Standard

General Description:

VTT connections were initially anticipated in the preliminary
XL pinouts to be IO voltage level connections to allow the
3.3volt XL devices, and future voltage migrations, to properly
interface the IO to other 5 volt devices.  Later testing showed
that these were not necessary for the 3.3 volt parts. As a
result the VTT connections for the 3.3volt XL parts were left
unbonded (N.C.).


Solution 1:

These VTT pins may become VCC connections later on so, users can either leave th
em unconnected, or tie them to VCC.



End of Record #1942