Rainbow Electronics ATF1504ASVL - Manual (Page 7)

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ATF1504ASV(L)
1409H–PLD–09/02
Figure 1. ATF1504ASV(L) Macrocell
Programmable Pin-keeper Option for Inputs and I/Os
The ATF1504ASV(L) offers the option of programming all input and I/O pins so that pin keeper circuits can be utilized.
When any pin is driven high or low and then subsequently left floating, it will stay at that previous high- or low-level. This cir-
cuitry prevents unused input and I/O lines from floating to intermediate voltage levels, which causes unnecessary power
consumption and system noise. The keeper circuits eliminate the need for external pull-up resistors and eliminate their DC
power consumption.