from
The Free On-line Dictionary of Computing (8 July 2008)
Programmable Array Logic
<hardware> (PAL) A family of fuse-programmable logic
{integrated circuits} originally developed by {MMI}.
Registered or {combinatorial} output functions are modelled in
a {sum of products} form. Each output is a sum (logical or)
of a fixed number of products (logical and) of the input
signals. This structure is well suited for automatic
generation of programming patterns by logic compilers.
PAL devices are programmed by blowing the fuses permanently
using overvoltage.
Today, more complex devices based on the same original
architecture are available (CPLD's for Complex PLD's) that
incorporate the equivalent of several original PAL chips. PAL
chips are, however, still popular due to their high speed.
{Generic Array Logic} devices are reprogrammable and contain
more {logic gates}.
(1995-12-09)