LC4256B-5FN256BI

Complex Programmable Logic Devices Overview

The LC4256B-5FN256BI is a Complex Programmable Logic Device (CPLD) belonging to the ispMACH 4000B family, manufactured by Lattice Semiconductor. It features 256 macrocells organized within 16 logic blocks and provides 141 available I/O pins. The device supports in-system programmability via JTAG and operates on an internal supply voltage ranging from 2.3V to 2.7V. It utilizes a 256-ball FineLine BGA package with a maximum propagation delay of 5ns. The component is rated for industrial temperature ranges, specifically operating between -40°C and +85°C.

Complex Programmable Logic Devices Feature Summary

• ispMACH 4000B architecture with 256 macrocells and 16 logic blocks
• In-system programmability (ISP) support via IEEE 1149.1 JTAG interface
• High-density I/O configuration with 141 user-accessible pins
• Low-voltage operation at 2.5V nominal (2.3V–2.7V range)
• FineLine BGA-256 package optimized for space-constrained designs

Complex Programmable Logic Devices Applications

• Interface bridging between legacy systems and modern low-voltage components
• Protocol conversion and data buffering in embedded systems
• Address decoding and control logic generation
• State machine implementation for industrial automation controllers

Complex Programmable Logic Devices Procurement Notes

Verify the specific suffix 'I' indicates the industrial temperature grade (-40°C to +85°C). Confirm the package type matches the required footprint, as FineLine BGA requires specialized reflow profiles. Check for end-of-life status or obsolescence notices from Lattice Semiconductor before finalizing procurement plans.

Complex Programmable Logic Devices Selection Notes

Select this model when 256 macrocells are sufficient for the design complexity. Ensure the PCB layout accommodates the 256-ball BGA pitch. Compare against the LC4256V series if lower power consumption is critical, noting that the V-series typically operates at higher voltages (3.0V–3.6V). Verify that the 5ns speed grade meets the timing requirements of the target application.

Complex Programmable Logic Devices Part Context

This part belongs to the ispMACH 4000B family, which succeeded the original ispMACH 4000 series. It offers enhanced performance and density compared to earlier generations while maintaining compatibility with existing programming tools like Radiant Design System. The B variant signifies improved speed grades and reliability features over the standard A version.

Complex Programmable Logic Devices Replacement Considerations

Direct pin-to-pin replacements may include other members of the LC4256B family with different speed grades (e.g., LC4256B-75) if timing constraints allow. Cross-family migration to LC5256MV requires schematic and code adaptation due to architectural differences.