参数资料
型号: 440GR
厂商: Applied Micro Circuits Corp.
英文描述: Power PC 440GR Embedded Processor
中文描述: 440GR的Power PC嵌入式处理器
文件页数: 72/82页
文件大小: 527K
代理商: 440GR
74
AMCC Proprietary
Revision 1.16 – July 19, 2006
Preliminary Data Sheet
440GR – PPC440GR Embedded Processor
DDR SDRAM Read Operation
The following examples of timing for DDR SDRAM read operations are based on the relationship between the
incoming data and the PLB clock signal. Since the PLB clock cannot be directly observed, the delay of
MemClkOut(0) relative to the PLB clock (TMD) is provided.
The internal Read Clock signal, like MemClkOut0, is derived from the PLB clock and can be delayed relative to the
PLB clock by programming the RDCT and RDCD fields in the SDRAM0_TR1 register. The delay can be
programmed from 0 to 1/2 cycle in steps using RDCT. Setting RDCD results in a 1/2 cycle delay plus the value set
in RDCT. The delay of Read Clock relative to the PLB clock (TRD) shown below assumes the programmable Read
Clock delay is set to zero.
Figure 9. DDR SDRAM MemClkOut0 and Read Clock Delay
In operation, following the receipt of an address and read command from the PPC440GR, the SDRAM generates
data and the DQS signals coincident with MemClkOut0. The data is latched into the PPC440GR using a DQS
signal that is delayed 1/4 of a cycle. In order to accommodate timing variations introduced by the system designs
using this chip, the three-stage data path shown below is used to eliminate metastability and allow data sampling to
be adjusted for minimum latency. This adjustment requires programming the Read Clock delay and the selection of
Stage 1, Stage 2, or Stage 3 data for sampling at RDSP.
Read Clock
PLB Clk
MemClkOut0(0)
TMD
TRD
TMDmin = 600ps
TMDmax = 1100ps
TRDmin = 300ps
TRDmax = 740ps
相关PDF资料
PDF描述
440GX Power PC 440GX Embedded Processor
440SPE PowerPC 440SPe Embedded Processor
440SP PowerPC 440SP Embedded Processor
4414-308 8 POS SOIC ADAPTER
4414-308LF 8 POS SOIC ADAPTER
相关代理商/技术参数
参数描述
440GRX 制造商:AMCC 制造商全称:Applied Micro Circuits Corporation 功能描述:PowerPC 440GRx Embedded Processor
440GS001NF1934-4 功能描述:环形MIL规格后盖 CRIMIP RING ADPTR DC STRAIGHT RoHS:否 制造商:Amphenol PCD MIL 类型:MIL-DTL-38999 III, IV 系列:AS85049 产品类型:Environmental EMI/RFI Backshells 外壳类型:Straight 外壳大小:18 外壳材质:Aluminum Alloy
440GS001NF2535-4 功能描述:环形MIL规格后盖 CRIMIP RING ADPTR DC STRAIGHT RoHS:否 制造商:Amphenol PCD MIL 类型:MIL-DTL-38999 III, IV 系列:AS85049 产品类型:Environmental EMI/RFI Backshells 外壳类型:Straight 外壳大小:18 外壳材质:Aluminum Alloy
440GS031B2912-4 制造商:Glenair Inc 功能描述:Shrink Boot Adapters 180° 29 Shell Size Olive Drab Cadmium Aluminum Direct 制造商:Glenair 功能描述:Shrink Boot Adapters 180° 29 Shell Size Olive Drab Cadmium Aluminum Direct
440GS031B3314-4 制造商:Glenair Inc 功能描述:Shrink Boot Adapters 180° 33 Shell Size Olive Drab Cadmium Aluminum Direct 制造商:Glenair 功能描述:Shrink Boot Adapters 180° 33 Shell Size Olive Drab Cadmium Aluminum Direct