Lattice LC4256V-75TN176: A Comprehensive Technical Overview of the CPLD

The Lattice LC4256V-75TN176 represents a significant component within the category of Complex Programmable Logic Devices (CPLDs). Designed for high-performance, low-power applications, this device offers a robust architecture that bridges the gap between simple PLDs and more complex FPGAs, making it an ideal solution for a wide array of control and logic integration tasks.

At the core of the LC4256V-75TN176 is an advanced logic architecture comprised of multiple Functional Blocks. Each block contains a programmable AND array that feeds a macrocells, providing the essential building blocks for implementing combinatorial and sequential logic. The device features 256 macrocells, a key metric that indicates its capacity to handle moderately complex logic designs. These macrocells are highly flexible, supporting various configurations including registered or combinatorial outputs with programmable polarity.

A critical aspect of this CPLD is its interconnect resources. A global routing pool connects all function blocks, allowing for predictable and fast signal propagation across the device. This deterministic timing is a hallmark of CPLD technology and is crucial for applications requiring precise logic operations without the routing delays typical in larger FPGAs.

The device is built on a 5.0V core voltage platform, with its I/O banks capable of supporting multiple voltage standards, a feature essential for interfacing with other components in a mixed-voltage system environment. The -75 speed grade denotes a maximum pin-to-pin delay of 7.5ns, ensuring high-speed operation for critical control paths. This makes it suitable for performance-oriented applications such as bus bridging, DMA control, and state machine implementation.

Housed in a 176-pin Thin Quad Flat Pack (TQFP) package, the LC4256V-75TN176 offers a substantial number of user I/O pins, facilitating connections to external memories, processors, and peripheral devices. The package is designed for surface-mount technology, making it suitable for automated assembly processes in high-volume production.

In-system programmability is achieved through a boundary-scan (JTAG) interface, which simplifies the development and debugging process. Designers can reprogram the device multiple times, enabling rapid prototyping and easy design iterations in the lab.

ICGOODFIND: The Lattice LC4256V-75TN176 is a powerful and reliable CPLD, offering a optimal blend of logic capacity, high-speed performance, and I/O flexibility. Its deterministic timing and non-volatile configuration make it a superior choice for critical control logic, system initialization, and glue logic applications in communications, computing, and industrial systems.

Keywords: CPLD, Programmable Logic, Macrocells, JTAG, TQFP