- 您现在的位置：买卖IC网 > PDF目录202172 > V54C3256404VDLJ6 (PROMOS TECHNOLOGIES INC) 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PBGA60 PDF资料下载
参数资料
| 型号： | V54C3256404VDLJ6 |
| 厂商： | PROMOS TECHNOLOGIES INC |
| 元件分类： | DRAM |
| 英文描述： | 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PBGA60 |
| 封装： | GREEN, MO-210, FBGA-60 |
| 文件页数： | 5/56页 |
| 文件大小： | 719K |
| 代理商： | V54C3256404VDLJ6 |
第1页第2页第3页第4页当前第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页
13
V54C3256(16/80/40)4VD Rev. 1.9 August 2008
ProMOS TECHNOLOGIES
V54C3256(16/80/40)4VD
Power On and Initialization
The default power on state of the mode register is
supplier specific and may be undefined. The
following power on and initialization sequence
guarantees the device is preconditioned to each
users specific needs. Like a conventional DRAM,
the Synchronous DRAM must be powered up and
initialized in a predefined manner. During power on,
all VCC and VCCQ pins must be built up
simultaneously to the specified voltage when the
input signals are held in the “NOP” state. The power
on voltage must not exceed VCC+0.3V on any of
the input pins or VCC supplies. The CLK signal
must be started at the same time. After power on,
an initial pause of 200
s is required followed by a
precharge of both banks using the precharge
command. To prevent data contention on the DQ
bus during power on, it is required that the DQM and
CKE pins be held high during the initial pause
period. Once all banks have been precharged, the
Mode Register Set Command must be issued to
initialize the Mode Register. A minimum of eight
Auto Refresh cycles (CBR) are also required.These
may be done before or after programming the Mode
Register. Failure to follow these steps may lead to
unpredictable start-up modes.
Programming the Mode Register
The Mode register designates the operation
mode at the read or write cycle. This register is di-
vided into 4 fields. A Burst Length Field to set the
length of the burst, an Addressing Selection bit to
program the column access sequence in a burst cy-
cle (interleaved or sequential), a CAS Latency Field
to set the access time at clock cycle and a Opera-
tion mode field to differentiate between normal op-
eration (Burst read and burst Write) and a special
Burst Read and Single Write mode. The mode set
operation must be done before any activate com-
mand after the initial power up. Any content of the
mode register can be altered by re-executing the
mode set command. All banks must be in pre-
charged state and CKE must be high at least one
clock before the mode set operation. After the mode
register is set, a Standby or NOP command is re-
quired. Low signals of RAS, CAS, and WE at the
positive edge of the clock activate the mode set op-
eration. Address input data at this timing defines pa-
rameters to be set as shown in the previous table.
Read and Write Operation
When RAS is low and both CAS and WE are high
at the positive edge of the clock, a RAS cycle starts.
According to address data, a word line of the select-
ed bank is activated and all of sense amplifiers as-
sociated to the wordline are set. A CAS cycle is
triggered by setting RAS high and CAS low at a
clock timing after a necessary delay, tRCD, from the
RAS timing. WE is used to define either a read
(WE = H) or a write (WE = L) at this stage.
SDRAM provides a wide variety of fast access
modes. In a single CAS cycle, serial data read or
write operations are allowed at up to a 125 MHz
data rate. The numbers of serial data bits are the
burst length programmed at the mode set operation,
i.e., one of 1, 2, 4, 8 and full page. Column address-
es are segmented by the burst length and serial
data accesses are done within this boundary. The
first column address to be accessed is supplied at
the CAS timing and the subsequent addresses are
generated automatically by the programmed burst
length and its sequence. For example, in a burst
length of 8 with interleave sequence, if the first ad-
dress is ‘2’, then the rest of the burst sequence is 3,
0, 1, 6, 7, 4, and 5.
Full page burst operation is only possible using
sequential burst type. Full Page burst operation
does not terminate once the burst length has been
reached. (At the end of the page, it will wrap to the
start address and continue.) In other words, unlike
burst length of 2, 4, and 8, full page burst continues
until it is terminated using another command.
相关PDF资料 |
PDF描述 |
|---|---|
| V54C3256404VDUI6 | 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PDSO54 |
| V54C3256404VDUS7 | 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PBGA60 |
| V54C3256404VHLI6I | 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PDSO54 |
| V54C3256404VHUI6I | 64M X 4 SYNCHRONOUS DRAM, 5.4 ns, PDSO54 |
| V54C3256804VBS7 | 32M X 8 SYNCHRONOUS DRAM, 5.4 ns, PBGA60 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| V54C3256404VS | 制造商:MOSEL 制造商全称:MOSEL 功能描述:256Mbit SDRAM 3.3 VOLT, TSOP II / SOC BGA / WBGA PACKAGE 16M X 16, 32M X 8, 64M X 4 |
| V54C3256404VT | 制造商:MOSEL 制造商全称:MOSEL 功能描述:256Mbit SDRAM 3.3 VOLT, TSOP II / SOC BGA / WBGA PACKAGE 16M X 16, 32M X 8, 64M X 4 |
| V54C3256804VAB | 制造商:MOSEL 制造商全称:MOSEL 功能描述:256Mbit SDRAM 3.3 VOLT, TSOP II / SOC BGA / WBGA PACKAGE 16M X 16, 32M X 8, 64M X 4 |
| V54C3256804VAT | 制造商:MOSEL 制造商全称:MOSEL 功能描述:256Mbit SDRAM 3.3 VOLT, TSOP II / SOC BGA / WBGA PACKAGE 16M X 16, 32M X 8, 64M X 4 |
| V54C3256804VB | 制造商:MOSEL 制造商全称:MOSEL 功能描述:256Mbit SDRAM 3.3 VOLT, TSOP II / SOC BGA / WBGA PACKAGE 16M X 16, 32M X 8, 64M X 4 |
发布紧急采购，3分钟左右您将得到回复。