Lattice LC4128C-75TN100C: A Comprehensive Technical Overview of the CPLD

The Lattice LC4128C-75TN100C is a high-performance, low-power Complex Programmable Logic Device (CPLD) from Lattice Semiconductor's ispMACH® 4000ZE family. This device is engineered to provide a flexible and cost-effective solution for a wide array of general-purpose logic integration tasks, serving as a critical glue logic component in complex digital systems. Its architecture is optimized for power-sensitive and space-constrained applications, making it a popular choice in consumer electronics, communications infrastructure, industrial control, and automotive systems.

At the core of the LC4128C lies a sophisticated macrocell-based architecture. The device features 128 macrocells, which are logically grouped into 4 blocks of 32 macrocells each. This structure allows for efficient routing and high pin-to-pin performance. Each macrocell can be independently configured for combinatorial or registered logic operations, providing designers with immense flexibility to implement various state machines, address decoders, and bus interfaces. The "75" in its part number signifies a maximum pin-to-pin delay of 7.5 ns, enabling its use in high-speed logic paths.

A key advantage of the ispMACH 4000ZE family, and this device in particular, is its ultra-low power consumption. Fabricated with an advanced CMOS process, it features a 1.8V core voltage with 3.3V I/O tolerance. This makes it ideal for battery-operated portable devices and other applications where minimizing power dissipation is a primary design constraint. The device also supports in-system programming (ISP) via the IEEE 1149.1 (JTAG) interface. This capability allows for reprogrammable logic functionality even after the device has been soldered onto a printed circuit board (PCB), significantly simplifying the prototyping, testing, and field-update processes.

The package type is denoted by "TN100C," indicating a 100-pin Thin Quad Flat Pack (TQFP). This surface-mount package offers a compact footprint, which is crucial for modern, dense PCB designs. The 100 pins provide up to 68 user-defined I/O pins, each of which can be configured to interface with various logic standards. These I/Os are organized into two banks, each capable of supporting different supply voltages, adding another layer of flexibility for interfacing with other components in a mixed-voltage environment.

Designing with this CPLD is supported by Lattice's ispLEVER® design software suite. This environment provides a complete flow from design entry (using schematic capture or VHDL/Verilog) to simulation, fitting, and finally, programming the device. The software tools efficiently manage the device's resources, including its programmable interconnect matrix, which routes signals between the logic blocks.

ICGOOODFIND: The Lattice LC4128C-75TN100C CPLD stands out as a highly versatile and efficient solution for logic consolidation. Its blend of high-speed performance (7.5ns), low-power 1.8V core operation, and reprogrammability via JTAG offers a compelling package for designers. The 100-pin TQFP package ensures it meets the size requirements of contemporary electronics, solidifying its role as a reliable workhorse for implementing critical glue logic, control functions, and interface bridging in a diverse range of electronic products.

Keywords: CPLD, Low-Power, JTAG Programming, Glue Logic, TQFP Package.