Lattice LC4128V-27TN100C: 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-27TN100C stands out as a robust and versatile solution from Lattice Semiconductor's high-performance family. This article provides a detailed technical examination of this specific component.

The LC4128V-27TN100C is built on a mature, high-speed CMOS technology that offers an optimal balance of power and performance. The "128" in its nomenclature signifies its core capacity, equating to 128 macrocells. These macrocells are the fundamental logic units, organized into four blocks, providing a flexible structure for implementing a wide range of combinatorial and sequential logic functions. This density makes it suitable for moderately complex tasks like address decoding, bus interfacing, state machine control, and I/O expansion.

A key attribute of this device is its non-volatile nature. Unlike FPGAs, which typically require an external boot PROM, the CPLD's configuration is stored on-chip in E²CMOS cells. This allows for instant-on operation upon power-up, a critical feature for system initialization and control applications where timing is paramount.

The performance of this component is highlighted by its speed grade. The "-27" suffix indicates a pin-to-pin logic delay of just 5.0 ns, enabling its use in high-speed systems. This fast performance is crucial for meeting critical timing constraints and ensures reliable operation in demanding environments.

The package type, TN100, denotes a 100-pin Thin Quad Flat Pack (TQFP). This surface-mount package offers a compact footprint, making it suitable for space-constrained PCB designs. The 100 pins provide a generous number of user I/Os, all of which are 5V tolerant, allowing for easy interfacing with legacy 5V systems without the need for level shifters. The device operates with a 3.3V core voltage, contributing to lower overall power consumption compared to 5V CPLDs.

Designing with the LC4128V is supported by Lattice's suite of development tools, including the ispLEVER software (now superseded by Lattice Radiant). These tools provide a complete design flow from HDL synthesis (VHDL/Verilog) and functional simulation to fitting, timing analysis, and programming.

ICGOOODFIND: The Lattice LC4128V-27TN100C is a highly capable CPLD that excels in providing fast, deterministic timing, non-volatile instant-on capability, and 5V tolerant I/Os in a compact package. It remains an excellent choice for control-oriented applications, legacy system upgrades, and any design requiring reliable and immediate logic execution.

Keywords: CPLD, Non-Volatile, 5V Tolerant, Macrocell, Deterministic Timing