ISPLSI 5256VA-125LQ208

Complex Programmable Logic Devices Overview

The ispLSI 5256VA-125LQ208 is a high-density, in-system programmable logic device from Lattice Semiconductor's ispLSI 5000V family. It features 256 macrocells and 192 I/O pins within a 208-pin Low Profile Quad Flat Package (LQFP). The device operates on a 3.3V supply with user-selectable 3.3V or 2.5V I/O levels. Key electrical specifications include a maximum operating frequency of 125 MHz and a propagation delay of 7.5 ns. It utilizes E2CMOS technology for non-volatile configuration and supports IEEE 1149.1 boundary scan testing.

Complex Programmable Logic Devices Feature Summary

• SuperWIDE Architecture: Features 32 Generic Logic Blocks (GLBs) with up to 35 product terms per macrocell via Product Term Sharing Array.
• High Performance: Achieves fmax = 125 MHz and tpd = 7.5 ns using E2CMOS technology.
• In-System Programmability: Supports reprogramming of soldered devices via IEEE 1149.1 JTAG interface.
• Flexible I/O: User-selectable 3.3V/2.5V output levels with programmable slew rates, bus hold, and pull-up resistors.

Complex Programmable Logic Devices Applications

• Complex state machine implementations requiring fast counters and address decoders.
• High-speed data processing systems utilizing the 125 MHz clock capability.
• Systems requiring in-circuit debugging and field updates without desoldering components.
• Interface bridging between standard 5V TTL devices and 3.3V logic families.

Complex Programmable Logic Devices Procurement Notes

Verify that the specific ordering suffix '-125LQ208' corresponds to the -125 speed grade (125 MHz) and the 208-pin LQFP package. Confirm the manufacturer is Lattice Semiconductor Corp. Ensure the component is genuine and not a counterfeit, as older PLD series may have limited new production availability.

Complex Programmable Logic Devices Selection Notes

Select this model when 256 macrocells and 192 I/Os are required in a low-profile surface-mount package. The -125 speed grade is necessary for designs exceeding 100 MHz. Consider the 272-ball BGA option if higher pin counts or better PCB thermal performance are needed instead of the LQFP form factor.

Complex Programmable Logic Devices Part Context

This component belongs to the ispLSI 5000V family, which succeeded earlier ispLSI 1000/2000/3000 series. It introduces enhanced Global Routing Pool (GRP) structures and SuperWIDE GLBs for improved pin locking and routing efficiency compared to previous generations.

Complex Programmable Logic Devices Replacement Considerations

Direct replacements must match the 256 macrocell count, 192 I/O limit, and 208-pin LQFP footprint. Verify voltage compatibility (3.3V core) and timing requirements (<= 7.5 ns). Cross-family migration to newer Lattice FPGA/CPLD lines requires schematic and code adaptation.

Complex Programmable Logic Devices FAQ

What is the difference between CLK0 and CLK1?

CLK0 is the dedicated master clock input with the lowest internal skew and no inversion. CLK1 can be inverted and shares pins with I/O signals depending on the package type.

How does the device handle 2.5V I/O levels?

The VCCIO pin allows independent selection of 3.3V or 2.5V output levels. The core logic remains powered at 3.3V, while the output drivers source/sink current based on the VCCIO reference.

Can unused inputs be left floating?

No. The device includes programmable pull-up resistors and bus-hold latches. Unused inputs should be configured with these features to prevent undefined states.