Lattice IM4A5-64-10VN-12I: A Comprehensive Technical Overview of the 64 Macrocell CPLD
The Lattice IM4A5-64-10VN-12I represents a specific implementation within a family of high-performance, low-power Complex Programmable Logic Devices (CPLDs) from Lattice Semiconductor. Designed for a wide array of general-purpose logic integration tasks, this device offers a balance of density, speed, and power efficiency, making it suitable for applications ranging from consumer electronics to industrial control systems.
Architectural Core: The Macrocell Array
At the heart of the IM4A5-64-10VN-12I is its core of 64 macrocells. Each macrocell consists of a programmable AND-array feeding into an OR-term and a configurable register (flip-flop). This structure allows for the efficient implementation of combinatorial and sequential logic functions. The macrocells are grouped into Functional Blocks (FBs), which are interconnected by a global programmable interconnect array (PIA). This PIA ensures a predictable, pin-to-pin timing delay, a hallmark of CPLD architecture, which simplifies high-speed design by eliminating routing-dependent delays.
Key Features and Performance
The part number itself encodes critical specifications. The `-10` speed grade denotes a pin-to-pin logic propagation delay (`tPD`) of 10 ns, enabling high-performance operation for control logic and state machines. The device features 36 user I/O pins (on the VN-100 package), providing ample connectivity for interfacing with other components like memories, sensors, and communication interfaces. These I/Os are compliant with various standards, offering flexibility in system design.
The device is built on Lattice's advanced 5V E²CMOS® technology. This technology provides several key advantages: it is in-system programmable (ISP) via a standard JTAG (IEEE 1149.1) interface, offers high noise immunity, and guarantees 100% tested programmability and functionality. The non-volatile E²CMOS cells retain the configuration upon power-down, eliminating the need for an external boot PROM.
Design and Development Support
Designing with the IM4A5-64-10VN-12I is supported by Lattice's ispLEVER® design environment. This software suite provides a complete set of tools for design entry (schematic or HDL), synthesis, functional and timing simulation, and fitting the design into the physical device. The predictable timing model of the CPLD architecture allows designers to achieve timing closure rapidly, significantly speeding up the development cycle compared to more complex FPGAs.
Target Applications
This CPLD is ideal for glue logic integration, where it can replace multiple simple PALs and discrete logic ICs, reducing board space and improving system reliability. Common use cases include:
Address decoding in microprocessor systems.
Bus interfacing and protocol bridging (e.g., between SPI and I²C).
State machine implementation for system control.
Simple data path control and signal conditioning.
The Lattice IM4A5-64-10VN-12I is a robust and reliable 64-macrocell CPLD, offering a compelling combination of high-speed performance, deterministic timing, and 5V operation. Its non-volatile, in-system programmable nature makes it a versatile and cost-effective solution for consolidating logic, simplifying board design, and accelerating time-to-market for a vast range of electronic systems.
Keywords:
1. CPLD (Complex Programmable Logic Device)
2. Macrocell
3. Programmable Interconnect Array (PIA)
4. In-System Programmable (ISP)
5. Deterministic Timing
