Overview

The EM6A9320 DDR SDRAM is a high-speed CMOS double data rate synchronous DRAM containing 128 Mbits. It is internally configured as a quad 1M x 32 DRAM with a synchronous interface (all signals are registered on the positive edge of the clock signal, CK). Data outputs occur at both rising edges of CK and CK#.

Read and write accesses to the SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence.

Accesses begin with the registration of a BankActivate command, which is then followed by a Read or Write command.

The EM6A9320 provides programmable Read or Write burst lengths of 2, 4, 8 and full page. An auto precharge function may be enabled to provide a self-timed row precharge that is initiated at the end of the burst sequence.

特性 Features

? Fast clock rate: 250/200/166 MHz

? Differential Clock CK & CK# input

? 4 Bi-directional DQS. Data transactions on both

edges of DQS (1DQS / Byte)

? DLL aligns DQ and DQS transitions

? Edge aligned data & DQS output

? Center aligned data & DQS input

? 4 internal banks, 1M x 32-bit for each bank

? Programmable mode and extended mode registers

- CAS Latency: 2, 2.5, 3, 4

- Burst length: 2, 4, 8, and Full Page

- Burst Type: Sequential & Interleave

? Full page burst length for sequential type only

? Start address of full page burst should be even

? All inputs except DQ’s & DM are at the positive

edge of the system clock

? No Write-Interrupted by Read function

? 4 individual DM control for write masking only

? Auto Refresh and Self Refresh

? 4096 refresh cycles / 32ms

? Power supplies :

VDD = 2.5V ± 5

VDDQ = 2.5V ± 5

? Interface : SSTL_2 I/O compatible

? Standard 144-ball FBGA package

? Pb-free package is availiable