ISPLSI 5256VE-125LT128I

Complex Programmable Logic Devices Overview

The ispLSI 5256VE-125LT128I is a high-density, in-system programmable logic device from Lattice Semiconductor's ispLSI 5000VE family. It features 256 macrocells and 12,000 PLD gates within a 128-pin Thin Quad Flat Package (TQFP). 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 165 MHz and a propagation delay of 6.0 ns. It utilizes E2CMOS technology for non-volatile storage and supports IEEE 1149.1 boundary scan testing.

Complex Programmable Logic Devices Feature Summary

• High-performance architecture with 165 MHz maximum frequency and 6.0 ns propagation delay
• In-system programmability via IEEE 1149.1 JTAG interface for manufacturing and debugging
• Dual voltage I/O capability allowing independent selection of 3.3V or 2.5V output levels
• SuperWIDE Generic Logic Blocks with Product Term Sharing Array supporting up to 35 product terms per function

Complex Programmable Logic Devices Applications

• Complex address decoding and state machine implementation
• High-speed counter circuits utilizing SuperWIDE input gating
• System control logic requiring reconfigurable hardware resources
• Interface bridging between standard 5V TTL devices and lower voltage logic

Complex Programmable Logic Devices Procurement Notes

Verify the specific suffix LT128I corresponds to the 128-pin TQFP package and industrial temperature range (-40°C to +85°C) as defined in the datasheet. Confirm that the -125 speed grade matches the required 6.0 ns timing constraints for the target application design.

Complex Programmable Logic Devices Selection Notes

Select this component when designs require high pin counts (up to 144 I/Os) and significant logic density within a single chip. Ensure the design fits within the 256 macrocell limit and utilizes the Global Routing Pool effectively. Consider the power consumption characteristics, which vary based on the number of active product terms and operating frequency.

Complex Programmable Logic Devices Part Context

This part belongs to the ispLSI 5000VE family, which succeeded the ispLSI 5000VA series. While pinouts may differ slightly from previous generations, programming and power/ground pins remain consistent. The VE family offers enhanced interconnect structures optimized for pin locking compared to earlier ispLSI 1000, 2000, and 3000 families.

Complex Programmable Logic Devices Replacement Considerations

Direct replacements must match the 256 macrocell count and 128-pin TQFP footprint. Note that the ispLSI 5000VA family is not JEDEC compatible due to architectural differences in macrocell optimization and removed features like programmable output-delay skew.