DP8421AV-25

Controllers Overview

The DP8421AV-25 is a dynamic random access memory (DRAM) controller manufactured by National Semiconductor. It supports a memory organization of 1M x 1 and features a 20-bit address bus width. The device operates with a maximum clock frequency of 25 MHz and includes a low-power mode. It is housed in a 68-pin Plastic Quad Flat Pack (PQCC) package, specifically identified as LCC-68, with dimensions of 24.2316 mm length and a maximum seated height of 5.08 mm. The component is rated for an operating temperature range from -40 °C to 70 °C.

Controllers Feature Summary

• Provides dedicated control logic for managing DRAM operations
• Integrates a 20-bit address bus interface for memory addressing
• Supports low-power operation modes for energy efficiency

Controllers Applications

• Embedded systems requiring external DRAM management
• Industrial control units with memory expansion needs
• Consumer electronics utilizing static memory architectures

Controllers Procurement Notes

Verify the specific suffix 'A' and '-25' against the manufacturer's current datasheet to confirm pinout compatibility and electrical specifications. Ensure the 68-pin PQCC/LCC package matches the target PCB footprint. Confirm that the 25 MHz maximum clock speed meets system timing requirements. Check for RoHS compliance status if environmental regulations apply to the final assembly.

Controllers Selection Notes

Select this component when a dedicated hardware solution for 1M x 1 DRAM interfacing is required without using a microcontroller. Consider the 25 MHz speed limit and 70 °C commercial temperature range during design. Evaluate the 68-pin package size constraints against available board space. Verify that the 20-bit address bus aligns with the target memory map architecture.

Controllers Part Context

This part belongs to the DP8421 series of DRAM controllers produced by National Semiconductor, which was later acquired by Texas Instruments. These controllers were designed to offload memory management tasks from central processors in embedded applications. The series typically offers various speed grades and package options to suit different performance and form factor requirements in legacy electronic designs.

Controllers Replacement Considerations

Consult official replacement lists for obsolete National Semiconductor components. Verify functional equivalence regarding the 68-pin LCC package and 25 MHz operation speed before substitution.