Lattice LC4128V-5TN100I: A Comprehensive Technical Overview of the CPLD

In the realm of digital logic design, Complex Programmable Logic Devices (CPLDs) remain a cornerstone for "glue logic," system configuration, and control applications. Among these, the Lattice LC4128V-5TN100I stands out as a robust and versatile solution, balancing density, performance, and power efficiency. This article provides a detailed technical examination of this specific CPLD.

The LC4128V is part of Lattice Semiconductor's high-performance, low-power ispMACH® 4000V CPLD family. The "128" in its designation signifies its capacity, containing 128 macrocells. These macrocells are the fundamental building blocks of the CPLD, each capable of implementing a combination of logic functions. The device is organized into four logic blocks, each containing 32 macrocells, interconnected by a sophisticated Global Routing Pool (GRP). This architecture ensures predictable timing and high-performance signal routing across the entire device.

A key feature of the ispMACH 4000V family is its 1.8V core voltage with 3.3V, 2.5V, or 1.8V I/O operation. The "-5" in the part number indicates a 5ns pin-to-pin logic propagation delay, enabling high-speed operation for a wide array of interface and control tasks. This combination of a low-voltage core and flexible I/O banks allows for significant power reduction without sacrificing performance, making it ideal for power-sensitive and portable applications.

The device packaging is denoted by "TN100I." This specifies a 100-pin Thin Quad Flat Pack (TQFP). This surface-mount package offers a compact footprint, which is crucial for modern, space-constrained PCB designs. The "I" suffix denotes the industrial temperature range, meaning the device is rated to operate reliably at ambient temperatures from -40°C to +100°C, ensuring robustness in demanding environments.

A defining advantage of this CPLD is its in-system programmability (ISP). Utilizing a standard 4-pin JTAG (IEEE 1149.1) interface, the device can be reprogrammed on the circuit board. This facilitates rapid design iterations, field upgrades, and easy debugging, drastically reducing development time and cost. The non-volatile E²CMOS® technology used for configuration ensures that the design is retained immediately upon power-up, with no external boot memory required.

Typical applications for the LC4128V-5TN100I are extensive. It is perfectly suited for:

Address decoding and bus interfacing in microprocessor systems.

System configuration and control for FPGAs and ASICs.

Protocol bridging and level translation between different logic families.

Function integration, replacing multiple discrete logic ICs to reduce board space and component count.

Power-on sequencing and management for complex systems.

ICGOOODFIND: The Lattice LC4128V-5TN100I is a highly capable CPLD that delivers an optimal blend of logic density, high-speed performance, and remarkably low power consumption. Its flexible I/O voltages, industrial-grade robustness, and in-system programmability make it an enduring and reliable choice for designers tackling a vast spectrum of digital control and interface challenges.

Keywords: CPLD, Low Power, In-System Programmability (ISP), 1.8V Core, TQFP Package