Lattice GAL26CV12C-10LJI: Architecture, Features, and Target Applications
The Lattice GAL26CV12C-10LJI stands as a classic example of a high-performance, low-power programmable logic device (PLD) from the Generic Array Logic (GAL) family. As an electrically erasable (EE) CMOS device, it offers a flexible and reliable solution for a wide range of digital logic integration tasks, combining the simplicity of standard logic with the customization of programmable devices.
Architecture
The architecture of the GAL26CV12C is centered around a programmable AND array feeding into a fixed OR array. This structure is a hallmark of Simple Programmable Logic Devices (SPLDs). The "26V12" designation indicates it has 26 inputs and 12 outputs. A key architectural feature is its Output Logic Macrocell (OLMC). Each of the 12 outputs is driven by a configurable OLMC, which can be programmed to operate in various modes: registered (clocked) or combinatorial (unclocked), and with active-high or active-low polarity. This macrocell-based architecture provides immense flexibility for implementing complex state machines and combinatorial logic functions. The `-10` speed grade denotes a maximum pin-to-pin delay of 10ns, ensuring swift signal propagation.
Key Features
The GAL26CV12C-10LJI is defined by a set of robust features designed for efficiency and ease of use.
High Performance: With a 10ns maximum propagation delay, it is capable of operating at high clock frequencies, making it suitable for timing-critical applications.
Low Power Consumption: Fabricated in advanced CMOS technology, it consumes significantly less power than its bipolar (e.g., PAL) predecessors, a critical factor for portable and battery-operated systems.
Electrically Erasable: The E²CMOS technology allows the device to be reprogrammed and erased electrically, facilitating rapid design iteration and prototyping without the need for UV erasure.
100% Testability: The device architecture supports 100% functional testability, ensuring high manufacturing yields and system reliability.
Package: The `LJI` suffix specifies a 28-lead PLCC (Plastic Leaded Chip Carrier) package, a common and robust surface-mount format for industrial applications.
Target Applications
The flexibility and reliability of the GAL26CV12C-10LJI have made it a staple across numerous industries for gluing together complex digital systems. Its primary role is often as a "glue logic" integrator, replacing multiple standard logic ICs (like the 7400-series) with a single, customized chip. Key application areas include:
Address Decoding: Generating chip select signals for microprocessors and microcontrollers in memory-mapped systems.
State Machine Design: Implementing finite state machines (FSMs) for control logic in various digital systems.
Bus Interface Logic: Acting as an interface between components with different signaling protocols or timing requirements.
I/O Expansion and Control: Managing input/output operations and data routing in embedded systems.
Military and Industrial Systems: Its proven reliability and wide operating temperature range make it suitable for harsh environment applications.
In summary, the Lattice GAL26CV12C-10LJI is a highly versatile and efficient SPLD. Its macrocell-based architecture, high speed, low power consumption, and reprogrammability have cemented its role as a fundamental component for logic integration and control in a vast array of electronic designs, from consumer electronics to critical industrial systems.
Keywords: Programmable Logic Device (PLD), Output Logic Macrocell (OLMC), Glue Logic, E²CMOS Technology, Address Decoding.
