Technical Summary: K4E661612D 4Mx16 EDO Mode DRAM

K4E661612D 4Mx16 EDO Mode DRAM Technical Summary

Overview

The K4E661612D is a high-performance 4Mx16 Extended Data Out (EDO) Mode Dynamic Random Access Memory (DRAM) component manufactured using Samsung's advanced CMOS process technology. This device belongs to a family of 3.3V DRAMs that offer enhanced bandwidth while maintaining low power consumption and high reliability. The component supports various refresh modes including CAS-before-RAS, RAS-only, Hidden refresh, and Self-refresh (in L-version variants). With its 16-bit wide data bus and EDO mode operation, this DRAM is designed for applications requiring efficient memory access in burst-oriented systems.

Key Features

Memory Organization: 4M words × 16 bits (67,108,864 bits total)
Operating Voltage: 3.3V ± 0.3V (LVTTL compatible)
Refresh Modes:
- CAS-before-RAS refresh capability
- RAS-only refresh capability
- Hidden refresh capability
- Self-refresh capability (L-version only)
EDO Mode Operation: Enables faster memory access cycles by maintaining valid data output after CAS transitions
Byte Control: 2 CAS (UCAS/LCAS) for byte/word read/write operations
Write Options: Supports both Early Write and Output Enable controlled write operations
Packaging: Available in Plastic TSOP(II) packages
Compatibility: JEDEC standard pinout for easy system integration
Test Capability: Fast parallel test mode for efficient production testing

Applications

The K4E661612D is suitable for a wide range of applications requiring medium-density DRAM with enhanced performance characteristics:

Computer systems and workstations
Networking equipment and routers
Telecommunications systems
Embedded systems requiring DRAM expansion
Graphics subsystems and display buffers
Industrial control systems
Test and measurement equipment

Electrical Characteristics

Absolute Maximum Ratings

Supply Voltage (Vcc): -0.5V to +4.6V
Input Voltage (Vin): -0.5V to Vcc+0.5V
Output Voltage (Vout): -0.5V to Vcc+0.5V
Operating Temperature: 0°C to +70°C (commercial)
Storage Temperature: -55°C to +125°C

Recommended Operating Conditions

Supply Voltage (Vcc): 3.0V to 3.6V
Input High Voltage (Vih): 2.0V min (Vcc=3.0V)
Input Low Voltage (Vil): 0.8V max (Vcc=3.0V)
Operating Temperature: 0°C to +70°C

DC Characteristics

Input Leakage Current (Ili): ±1μA max
Output Leakage Current (Ilo): ±1μA max
Operating Current (Icc1): 120mA max (active)
Standby Current (Icc2): 20mA max (RAS = VIH)
Refresh Current (Icc3): 30mA max
Self-Refresh Current (Icc4): 2mA max (L-version only)

AC Characteristics

RAS Precharge Time (tRP): 20ns min
RAS to CAS Delay (tRCD): 20ns min
CAS Pulse Width (tCAS): 20ns min
CAS Precharge Time (tCP): 20ns min
Access Time from CAS (tCAC): 15ns max
Access Time from RAS (tRAC): 60ns max
Write Pulse Width (tWP): 15ns min
Data Hold Time (tDH): 10ns min

Functional Description

The K4E661612D features a standard DRAM architecture with enhanced EDO mode operation. The memory array is divided into upper and lower banks, each controlled by separate CAS signals (UCAS and LCAS) for byte operations. The device incorporates internal sense amplifiers, row and column decoders, and refresh control circuitry.

Refresh Operation

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

CAS-before-RAS Refresh: Initiated by asserting CAS before RAS
RAS-only Refresh: Single RAS cycle refresh operation
Hidden Refresh: Refresh cycle that can be combined with a read or write operation
Self Refresh: Available in L-version, maintains data without external refresh commands

EDO Mode Operation

In Extended Data Out mode, the output data remains valid after CAS goes high, allowing the next cycle to begin while the current data is still being read. This pipelining effect improves memory bandwidth compared to conventional DRAMs.