Texas Instruments TMS320DM355 Manual Do Utilizador
www.ti.com
PRODUCT PREVIEW
5.7.2
DDR2 Memory Controller
TMS320DM355
Digital Media System-on-Chip (DMSoC)
Digital Media System-on-Chip (DMSoC)
SPRS463A – SEPTEMBER 2007 – REVISED SEPTEMBER 2007
The DDR2 / mDDR Memory Controller is a dedicated interface to DDR2 / mDDR SDRAM. It supports
JESD79D-2A standard compliant DDR2 SDRAM devices and compliant Mobile DDR SDRAM devices.
DDR2 / mDDR SDRAM plays a key role in a DM355-based system. Such a system is expected to require
a significant amount of high-speed external memory for all of the following functions:
JESD79D-2A standard compliant DDR2 SDRAM devices and compliant Mobile DDR SDRAM devices.
DDR2 / mDDR SDRAM plays a key role in a DM355-based system. Such a system is expected to require
a significant amount of high-speed external memory for all of the following functions:
•
Buffering of input image data from sensors or video sources
•
Intermediate buffering for processing/resizing of image data in the VPFE
•
Numerous OSD display buffers
•
Intermediate buffering for large raw Bayer data image files while performing image processing
functions
functions
•
Buffering for intermediate data while performing video encode and decode functions
•
Storage of executable code for the ARM
The DDR2 / mDDR Memory Controller supports the following features:
•
JESD79D-2A standard compliant DDR2 SDRAM
•
Mobile DDR SDRAM
•
256 MByte memory space
•
Data bus width 16 bits
•
CAS latencies:
–
–
DDR2: 2, 3, 4, and 5
–
mDDR: 2 and 3
•
Internal banks:
–
–
DDR2: 1, 2, 4, and 8
–
mDDR: 1, 2, and 4
•
Burst length: 8
•
Burst type: sequential
•
1 CS signal
•
Page sizes: 256, 512, 1024, and 2048
•
SDRAM autoinitialization
•
Self-refresh mode
•
Partial array self-refresh (for mDDR)
•
Power down mode
•
Prioritized refresh
•
Programmable refresh rate and backlog counter
•
Programmable timing parameters
•
Little endian
For details on the DDR2 Memory Controller, refer to the DDR/mDDR Peripheral Reference Guide.
5.7.2.1 DDR2/mDDR Memory Controller Electrical Data/Timing
TI only supports DDR2/mDDR board designs that follow the guidelines described in the application note
titled TMS320DM355 DDR2 / mDDR Board Design Application Note. Refer to this application note for
information on board design recommendations and guidelines for DDR2 and mDDR.
titled TMS320DM355 DDR2 / mDDR Board Design Application Note. Refer to this application note for
information on board design recommendations and guidelines for DDR2 and mDDR.
Peripheral Information and Electrical Specifications
112