7

ATF22V10C(Q)

0735P–PLD–01/02

Input and I/O Pin-

keeper Circuits

The ATF22V10C contains internal input and I/O pin-keeper circuits. These circuits allow

each ATF22V10C pin to hold its previous value even when it is not being driven by an

external source or by the device’s output buffer. This helps to ensure that all logic array

inputs are at known valid logic levels. This reduces system power by preventing pins

from floating to indeterminate levels. By using pin-keeper circuits rather than pull-up

resistors, there is no DC current required to hold the pins in either logic state (high or

low).

These pin-keeper circuits are implemented as weak feedback inverters, as shown in the

Input Diagram below. These keeper circuits can easily be overdriven by standard TTL-

or CMOS-compatible drivers. The typical overdrive current required is 40 µA.

Input Diagram

I/O Diagram