Lattice LC4256V-75TN144-10I: A Comprehensive Technical Overview of the CPLD

The Lattice LC4256V-75TN144-10I is a high-performance, low-power Complex Programmable Logic Device (CPLD) from Lattice Semiconductor's mature ispMACH 4000V family. This device is engineered to provide a flexible and reliable logic integration solution for a wide array of applications, from communication interfaces to industrial control systems. Its architecture is optimized for complex state machine control, address decoding, and high-speed glue logic, serving as a critical component in system-level designs.

Architectural Core: The ispMACH 4000V Structure

At the heart of the LC4256V lies the advanced ispMACH 4000V CPLD architecture. This device features 256 macrocells, which are partitioned into four logic blocks. Each macrocell can be independently configured for registered or combinatorial logic operations, offering significant design flexibility. The core is built on a 5-nanosecond pin-to-pin logic delay, enabling high-speed data processing and making it suitable for timing-critical applications. The internal interconnect is a deterministic, predictable routing scheme, which eliminates the routing uncertainties common in FPGAs and guarantees stable performance once a design is compiled.

Key Specifications and Performance

The part number itself, LC4256V-75TN144-10I, provides essential information:

LC4256V: Denotes the family (4000V) and the macrocell count (256).

-75: Indicates a maximum propagation delay (tPD) of 7.5 ns, ensuring high-speed operation.

-10I: Specifies the industrial-grade temperature range (-40°C to +100°C), making it robust for harsh environments.

TN144: Refers to the 144-pin Thin Quad Flat Pack (TQFP) package, which is a surface-mount package with a low profile, ideal for space-constrained PCB designs.

The device operates on a 3.3V core voltage with 5V tolerant I/Os, allowing for easy interfacing with both older 5V and newer 3.3V systems. It supports in-system programmability (ISP) through the IEEE 1149.1 (JTAG) interface, allowing for convenient field upgrades and prototype debugging without removing the chip from the circuit board.

Design Advantages and Target Applications

The primary advantages of this CPLD include its non-volatile configuration memory, meaning it instantly boots upon power-up without needing an external configuration chip. This feature is crucial for systems requiring immediate operation. Its deterministic timing model simplifies the design process, as signal delays are fixed and predictable.

These characteristics make the LC4256V-75TN144-10I an excellent choice for a diverse set of applications:

Telecommunications: Handles protocol bridging, interface logic, and control functions in network equipment.

Industrial Automation: Implements motor control, I/O expansion, and custom state machines for programmable logic controllers (PLCs).

Consumer Electronics: Manages logic consolidation, power sequencing, and system configuration in sophisticated electronic products.

Automotive Systems: Used in subsystems that require reliable, instant-on performance under a wide temperature range.

Development Ecosystem

Designing with this CPLD is supported by Lattice's ispLEVER classic design software. This environment provides a complete suite of tools, including synthesis, place-and-route, and verification features, allowing engineers to efficiently create, simulate, and program their designs.

ICGOOODFIND: The Lattice LC4256V-75TN144-10I CPLD stands as a testament to the enduring value of proven programmable logic technology. It delivers an optimal blend of high speed, low power consumption, and design reliability. Its non-volatile nature and deterministic timing offer a straightforward and robust alternative to more complex FPGAs for a vast number of glue logic and control-oriented tasks. For engineers seeking a dependable, industry-workhorse CPLD for industrial, communications, or automotive applications, the LC4256V-75TN144-10I remains a compelling and powerful solution.

Keywords:

1. CPLD

2. Macrocell

3. Non-Volatile

4. ispLEVER

5. JTAG