参数资料
型号: W9725G6IB-18
厂商: WINBOND ELECTRONICS CORP
元件分类: DRAM
英文描述: 16M X 16 DDR DRAM, 0.35 ns, PBGA84
封装: 8 X 12.50 MM, ROHS COMPLIANT, WBGA-84
文件页数: 13/69页
文件大小: 1644K
代理商: W9725G6IB-18
PRELIMINARY W9725G6IB
Publication Release Date:Nov. 14, 2008
- 20 -
Revision P04
7.3. Command Function
7.3.1.
Bank Activate Command
(
CS = "L", RAS = "L", CAS = "H", WE = "H", BA0, BA1 = Bank, A0 to A12 be row address)
The Bank Activate command must be applied before any Read or Write operation can be executed.
Immediately after the bank active command, the DDR2 SDRAM can accept a read or write command
on the following clock cycle. If a Read/Write command is issued to a bank that has not satisfied the
tRCDmin specification, then additive latency must be programmed into the device to delay when the
Read/Write command is internally issued to the device. The additive latency value must be chosen to
assure tRCDmin is satisfied. Additive latencies of 0, 1, 2, 3, 4, 5 and 6 are supported. Once a bank has
been activated it must be precharged before another Bank Activate command can be applied to the
same bank. The bank active and precharge times are defined as tRAS and tRP, respectively. The
minimum time interval between successive Bank Activate commands to the same bank is determined
by the RAS cycle time of the device (tRC). The minimum time interval between Bank Activate
commands is tRRD.
T0
T1
T2
T3
Tn
Tn+1
Tn+2
Tn+3
Bank A
Row Addr.
Bank A
Col. Addr.
Bank B
Row Addr.
Bank B
Col. Addr.
Bank A
Addr.
Bank B
Addr.
Bank A
Row Addr.
CAS - CAS delay time(tCCD)
tRCD = 1
Additive Latency delay(AL)
Read Begins
Bank A
Activate
Bank A
Post CAS
Read
Bank B
Activate
Bank B
Post CAS
Read
Bank A
Precharge
Bank B
Precharge
Bank A
Activate
Bank Active (
≧tRAS)
RAS Cycle time (
≧tRC)
Bank Precharge time (
≧tRP)
Command
Address
RAS - RAS delay time(
≧tRRD)
CLK
Internal RAS - RAS delay (
≧tRCDmin)
Figure 12
—Bank activate command cycle: tRCD = 3, AL = 2, tRP = 3, tRRD = 2, tCCD = 2
7.3.2.
Read Command
(
CS = "L", RAS = "H", CAS = "L", WE = "H", BA0, BA1 = Bank, A10 = "L", A0 to A8 = Column
Address)
The READ command is used to initiate a burst read access to an active row. The value on BA0, BA1
inputs selects the bank, and the A0 to A8 address inputs determine the starting column address. The
address input A10 determines whether or not Auto-precharge is used. If Auto-precharge is selected,
the row being accessed will be precharged at the end of the READ burst; if Auto-precharge is not
selected, the row will remain open for subsequent accesses.
7.3.3.
Write Command
(
CS = "L", RAS = "H", CAS = "L", WE = "L", BA0, BA1 = Bank, A10 = "L", A0 to A8 = Column
Address)
The WRITE command is used to initiate a burst write access to an active row. The value on BA0, BA1
inputs selects the bank, and the A0 to A8 address inputs determine the starting column address. The
address input A10 determines whether or not Auto-precharge is used. If Auto-precharge is selected,
相关PDF资料
PDF描述
W9864G6EB-7 4M X 16 SYNCHRONOUS DRAM, 5.5 ns, PBGA60
WE128K8200CQ 128K X 8 EEPROM 5V MODULE, 200 ns, CDIP32
WED9LC6816V1512BI SPECIALTY MEMORY CIRCUIT, PBGA153
WS128K32-35G2TMEA 128K X 32 MULTI DEVICE SRAM MODULE, 35 ns, CQFP68
WS128K32-55G2TIE 128K X 32 MULTI DEVICE SRAM MODULE, 55 ns, CQFP68
相关代理商/技术参数
参数描述
W9725G6IB-25 功能描述:IC DDR2-800 SDRAM 256MB 84-WBGA RoHS:是 类别:集成电路 (IC) >> 存储器 系列:- 标准包装:1,000 系列:- 格式 - 存储器:EEPROMs - 串行 存储器类型:EEPROM 存储容量:4K (512 x 8) 速度:400kHz 接口:I²C,2 线串口 电源电压:2.7 V ~ 5.5 V 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC(0.173",4.40mm 宽) 供应商设备封装:8-MFP 包装:带卷 (TR)
W9725G6JB 制造商:WINBOND 制造商全称:Winbond 功能描述:4M ? 4 BANKS ? 16 BIT DDR2 SDRAM
W9725G6JB-25 制造商:Winbond Electronics Corp 功能描述:DRAM Chip DDR2 SDRAM 256M-Bit 16Mx16 1.8V 84-Pin WBGA 制造商:Winbond Electronics 功能描述:512MB DDRII
W9725G6JB25I 功能描述:IC DDR2 SDRAM 256MBIT 84WBGA RoHS:是 类别:集成电路 (IC) >> 存储器 系列:- 标准包装:150 系列:- 格式 - 存储器:EEPROMs - 串行 存储器类型:EEPROM 存储容量:4K (2 x 256 x 8) 速度:400kHz 接口:I²C,2 线串口 电源电压:2.5 V ~ 5.5 V 工作温度:-40°C ~ 85°C 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-DFN(2x3) 包装:管件 产品目录页面:1445 (CN2011-ZH PDF)
W9725G6KB-18 制造商:Winbond Electronics 功能描述:IC MEMORY 制造商:Winbond Electronics Corp 功能描述:IC MEMORY