PAL architecture — path of product terms in combinational mode In a typical programmable array logic (PAL), each gate product term is ORed, and for combinational logic the resulting sum is then:

Introduction / Context:
PAL devices use a programmable AND array followed by a fixed OR array. Understanding the signal path in combinational mode clarifies how polarity and buffering are handled before a logic signal reaches the output pin.

Given Data / Assumptions:

• PAL: programmable AND array + fixed OR array.
• Combinational mode (no register stage).
• Output polarity and buffering are typically provided by an output inverter/buffer.

Concept / Approach:
Product terms are generated in the AND array. These terms are summed by the OR array to form the desired logic function. In standard PALs, the summed signal passes through an output buffer/inverter whose polarity may be programmable (via a “polarity fuse”). Thus, in combinational mode, the ORed signal does not go raw to the pin; it is routed through an inverter/buffer stage first.

Step-by-Step Solution:

Verification / Alternative check:
Check canonical PAL block diagrams: after the OR array, an inversion/polarity option is shown before the pad.

Why Other Options Are Wrong:

• C: Skips the essential output buffer/inverter stage.
• D: Signal does not return to the AND plane after ORing.
• A: “Polarity fuse is restored” is not an operation step; polarity is configured, not dynamically restored.

Common Pitfalls:
Confusing PAL with PLA or GAL variants; while implementations differ, the output buffer/inverter remains standard in combinational mode.

Final Answer:
sent to an inverter for output