IDT71P71804S250BQ

Memory IC Overview

The IDT71P71804S250BQ is an 18Mb synchronous DDR II SRAM with a 1M x 18 organization. It features a common bidirectional data port and multiplexed address bus, supporting two-word bursts per clock cycle. The device operates at a maximum clock frequency of 250 MHz with a 6.3 ns access time. It utilizes a 165-ball CABGA package measuring 13mm x 15mm. Core voltage (VDD) ranges from 1.7V to 1.9V, while I/O supply (VDDQ) scales from 1.4V to 1.9V. Operating temperature is specified from 0°C to +70°C.

Memory IC Feature Summary

• Supports double-data-rate (DDR) bidirectional data transfers with a burst of two words per clock cycle.
• Features scalable output impedance adjustable via an external resistor to match system transmission lines.
• Includes dual echo clock outputs for precise data valid indication and duty cycle improvement.
• Integrates a DLL for tight alignment between input clocks and output data.

Memory IC Applications

• High-speed networking equipment requiring low-latency buffering
• Telecommunications systems utilizing parallel interface architectures
• Industrial control systems needing real-time data processing

Memory IC Procurement Notes

Verify the specific speed grade suffix matches the required clock frequency, as the base part number covers multiple variants. Confirm that the 165-CABGA footprint aligns with the target PCB design. Ensure power delivery supports the 1.8V core and scalable VDDQ requirements. Check for RoHS compliance status if environmental regulations apply to the end product.

Memory IC Selection Notes

Select this component when a high-bandwidth, low-latency memory solution with a wide data bus is required. The 1M x 18 configuration suits applications needing parallel data paths. Consider the programmable impedance feature for signal integrity optimization in complex board layouts. Verify compatibility with HSTL or scaled voltage interfaces for the host controller.

Memory IC Part Context

This device belongs to the IDT71P71 family of DDR II Burst of Two SRAMs. Other members include the IDT71P71204 (2Mx8), IDT71P71104 (2Mx9), and IDT71P71604 (512Kx36). All share similar architectural features but differ in bit-width and depth configurations within the same 165-ball package.

Memory IC Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Consult manufacturer resources for obsolescence management or cross-reference alternatives based on pinout and electrical specifications.

Memory IC FAQ

How is the output drive impedance adjusted?

An external resistor (RQ) connects the ZQ pin to ground. The output impedance is set to 0.2 times the RQ value, allowing adjustment between 35 ohms and 70 ohms.

What is the function of the SA0 pin on the IDT71P71804?

SA0 serves as a burst count address bit, allowing the user to reverse the burst order or address individual words within a burst during read or write operations.