Lattice GAL16V8B-10LP: Architecture, Key Features, and Typical Applications

The Lattice GAL16V8B-10LP stands as a quintessential example of a high-performance, low-power programmable logic device (PLD) that has served as a fundamental building block in countless digital designs. As a member of the Generic Array Logic (GAL) family, it provides a flexible and reliable alternative to fixed-function logic ICs. Its architecture, optimized for a wide range of applications, combines efficiency with ease of use.

Architecture

The architecture of the GAL16V8B-10LP is centered around a programmable AND array feeding into fixed OR arrays and sophisticated output logic macrocells (OLMCs). The "16" in its name denotes the number of inputs, while the "8" represents the maximum number of outputs. The heart of the device is the programmable AND array, which generates product terms (a combination of inputs and their complements). These product terms are then routed to the OR array and the OLMCs.

Each of the eight outputs is configured through its own OLMC. A key architectural advantage is that each output can be individually configured as a combinatorial (non-registered) or registered (clocked) output. This flexibility allows the same device to implement simple glue logic or more complex sequential state machines. The global clock (Pin 1) and output enable (Pin 11) signals provide central control for all registered functions and three-state outputs, respectively.

Key Features

The GAL16V8B-10LP is defined by a set of features that made it exceptionally popular:

High Performance: The "-10" suffix indicates a maximum propagation delay of 10 ns, enabling operation at high clock speeds for its category.

Low Power (LP): Fabricated in low-power CMOS technology, it consumes significantly less power than its bipolar (e.g., PAL) predecessors, making it suitable for power-sensitive applications.

Electrically Erasable: The use of EECMOS (Electrically Erasable CMOS) technology makes the device reprogrammable and highly reusable. Designs can be revised and tested无数次 without removing the chip from the circuit board.

100% Testability: The built-in logic functionality and programmable registers ensure that the device can be thoroughly tested for manufacturing defects.

High Reliability: The CMOS construction offers high noise immunity and a wide operating voltage range.

Typical Applications

The reprogrammability and density of the GAL16V8B-10LP made it ideal for integrating multiple simple logic functions into a single chip. Its most common applications include:

Address Decoding: Generating chip select (CS) and read/write (R/W) signals for microprocessors and memory systems.

State Machine Control: Implementing finite state machines (FSMs) for controlling digital systems.

Bus Interface Logic: Acting as an interface between components with different signaling protocols or timing requirements.

Glue Logic Integration: Replacing multiple small- and medium-scale integration (SSI/MSI) ICs like 74-series logic gates, latches, and registers, thereby reducing board space and component count.

ICGOODFIND: The Lattice GAL16V8B-10LP is a classic, low-power PLD that exemplifies the shift from fixed TTL logic to programmable solutions. Its blend of a flexible macrocell architecture, high speed, and CMOS low-power characteristics solidified its role as a go-to component for logic integration, system control, and interface management in a vast array of electronic products.

Keywords: Programmable Logic Device (PLD), Output Logic Macrocell (OLMC), Electrically Erasable, Glue Logic, Address Decoding