- 您现在的位置：买卖IC网 > PDF目录98149 > STPCI2HDYI (STMICROELECTRONICS) MULTIFUNCTION PERIPHERAL, PBGA516 PDF资料下载
参数资料
| 型号： | STPCI2HDYI |
| 厂商： | STMICROELECTRONICS |
| 元件分类： | 外设及接口 |
| 英文描述： | MULTIFUNCTION PERIPHERAL, PBGA516 |
| 封装： | PLASTIC, BGA-516 |
| 文件页数： | 104/109页 |
| 文件大小： | 2430K |
| 代理商： | STPCI2HDYI |
第1页第2页第3页第4页第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页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页当前第104页第105页第106页第107页第108页第109页
STPC ATLAS
94/109
Issue 1.1 - March 23, 2004
The maximum skew between pins for this part is
250ps. The important factors for the clock buffer
are a consistent drive strength and low skew
between the outputs. The delay through the buffer
is not important so it does not have to be a zero
delay PLL type buffer. The trace lengths from the
clock driver to the DIMM CKn pins should be
matched exactly. Since the propagation speed
can vary between PCB layers, the clocks should
be routed in a consistent way. The routing to the
STPC memory input should be longer by 75 mm to
compensate for the extra clock routing on the
DIMM. Also a 20 pF capacitor should be placed as
near as possible to the clock input of the STPC to
compensate for the DIMM’s higher clock load. The
impedance of the trace used for the clock routing
should be matched to the DIMM clock trace
impedance (60-75 ohms)
.To minimise crosstalk
the clocks should be routed with spacing to
adjacent tracks of at least twice the clock trace
width. For designs which use SDRAMs directly
mounted on the motherboard PCB all the clock
trace lengths should be matched to the constraints
given in Figure 6-23 and in Section 4.5.3. .
The DIMM sockets should be populated starting
with the furthest DIMM from the STPC device first
(DIMM1). There are two types of DIMM devices;
single-row and dual-row. The dual-row devices
require two chip select signals to select between
the two rows. A STPC device with 4 chip select
control lines could control either 4 single-row
DIMMs or 2 dual-row DIMMs. When only 2 chip
select control lines are activated, only two single-
row DIMMs or one dual-row DIMM can be
controlled.
6.4.3.4. Summary
For unbuffered DIMMs the address/control signals
will be the most critical for timing. The simulations
show that for these signals the best way to drive
them is to use a parallel termination. For
applications where speed is not so critical series
termination can be used as this will save power.
Using a low impedance such as 50
for these
critical traces is recommended as it both reduces
the delay and the overshoot.
The other memory interface signals will typically
be not as critical as the address/control signals.
Using lower impedance traces is also beneficial
for the other signals but if their timing is not as
critical as the address/control signals they could
use the default value. Using a lower impedance
implies using wider traces which may have an
impact on the routing of the board.
The layout of this interface can be validated by an
electrical
simulation
using
the
IBIS
model
available on the STPC web site.
6.5. CLOCK TOPOLOGY FOR ON-BOARD
SDRAM
Figure 4-5 and Figure 6-25 give the recommended
clock topology and the resulting IBIS simulation in
the case of four on-board SDRAM devices and no
clock buffer.
Figure 6-24. Recommended topology for 4 on-board SDRAMs (IBIS model)
MCLKI
MCLKO
18 Ohms
400 mils
3500 mils
400 mils
MCLK0
MCLK1
MCLK2
MCLK3
Track impedance= 75 Ohms
Trace thickness = 0.72 mil
Trace width = 4 to 8 mils
相关PDF资料 |
PDF描述 |
|---|---|
| STPCI2HEYI | MULTIFUNCTION PERIPHERAL, PBGA516 |
| STPCI2HDYC | MULTIFUNCTION PERIPHERAL, PBGA516 |
| STPIC6C595M | 8-BIT RIGHT SERIAL IN PARALLEL OUT SHIFT REGISTER, TRUE OUTPUT, PDSO16 |
| STR710RZT6 | 32-BIT, FLASH, 66 MHz, RISC MICROCONTROLLER, PQFP144 |
| STUF32864EHLFT | SSTU SERIES, POSITIVE EDGE TRIGGERED D FLIP-FLOP, TRUE OUTPUT, PBGA96 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| STPCI2HEYC | 功能描述:微处理器 - MPU 133MHz x86 SoC RoHS:否 制造商:Atmel 处理器系列:SAMA5D31 核心:ARM Cortex A5 数据总线宽度:32 bit 最大时钟频率:536 MHz 程序存储器大小:32 KB 数据 RAM 大小:128 KB 接口类型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作电源电压:1.8 V to 3.3 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-324 |
| STPCI2HEYI | 功能描述:微处理器 - MPU 133MHz x86 SoC RoHS:否 制造商:Atmel 处理器系列:SAMA5D31 核心:ARM Cortex A5 数据总线宽度:32 bit 最大时钟频率:536 MHz 程序存储器大小:32 KB 数据 RAM 大小:128 KB 接口类型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作电源电压:1.8 V to 3.3 V 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:FBGA-324 |
| STPCINDUSTRIAL | 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:PC Compatible Embedded Microprocessor |
| STP-CN04 | 功能描述:烙铁 Cartridge Conical 0.4mm (0.016in) RoHS:否 制造商:Weller 产品:Soldering Stations 类型:Digital, Iron, Stand, Cleaner 瓦特:50 W 最大温度:+ 850 F 电缆类型:US Cord Included |
| STP-CN05 | 功能描述:烙铁 Cartridge Conical 0.5mm (0.02in) RoHS:否 制造商:Weller 产品:Soldering Stations 类型:Digital, Iron, Stand, Cleaner 瓦特:50 W 最大温度:+ 850 F 电缆类型:US Cord Included |
发布紧急采购，3分钟左右您将得到回复。