K4E641612D Technical Summary

K4E641612D 4Mx16 EDO Mode DRAM

Overview

The K4E641612D is a 4Mx16 Extended Data Out (EDO) Mode Dynamic Random Access Memory (DRAM) component manufactured using Samsung's advanced CMOS process technology. This high-performance memory device offers 64Mb (4M words x 16 bits) organization with EDO mode operation for improved bandwidth compared to conventional DRAMs. The device operates at 3.3V and features multiple refresh modes including self-refresh capability in the L-version variant.

Designed for applications requiring high bandwidth and low power consumption, the K4E641612D provides LVTTL-compatible inputs and outputs while maintaining high reliability. The device is available in industry-standard TSOP(II) packages and supports various advanced features including multiple refresh modes and fast parallel testing.

Key Features

64Mb organization (4M words × 16 bits)
Extended Data Out (EDO) Mode operation for improved bandwidth
3.3V ±0.3V power supply (LVTTL compatible)
Multiple refresh modes:
- CAS-before-RAS refresh
- RAS-only refresh
- Hidden refresh
- Self-refresh capability (L-version only)
2 CAS (UCAS/LCAS) Byte/Word Read/Write operation
Early Write or output enable controlled write options
Fast parallel test mode capability
JEDEC standard pinout configuration
Available in Plastic TSOP(II) packages
4K refresh cycles (K4E641612D variant)

Applications

The K4E641612D is suitable for a wide range of applications requiring moderate density DRAM with improved bandwidth characteristics:

Computer systems and workstations
Networking equipment
Telecommunications systems
Embedded systems requiring DRAM memory
Industrial control systems
Graphics subsystems
Test and measurement equipment

The EDO mode operation makes this device particularly suitable for applications where burst memory access patterns are common, as it eliminates the need to insert wait states between consecutive memory accesses within a page.

Functional Description

Architecture

The K4E641612D features a 4Mx16 organization with two independent 8-bit data paths controlled by upper and lower CAS signals (UCAS and LCAS). This architecture allows for byte-wide (8-bit) or word-wide (16-bit) operations. The memory array is divided into upper and lower banks, each with its own data input and output buffers.

Refresh Modes

The device supports multiple refresh strategies to accommodate different system requirements:

CAS-before-RAS Refresh: The traditional DRAM refresh method where CAS is asserted before RAS
RAS-only Refresh: Refresh initiated by RAS assertion alone
Hidden Refresh: Refresh that can occur during active operation
Self-Refresh: Available in L-version, allowing the device to manage its own refresh cycles during low-power states

Data Operations

The EDO mode operation allows the data outputs to remain valid after CAS goes inactive, as long as RAS remains active. This enables the next memory access to begin while the current data is still being read, improving overall memory bandwidth. The device supports both early write and output enable controlled write operations for flexibility in system design.