AT91SAM9G45-CU-999 Atmel, AT91SAM9G45-CU-999 Datasheet - Page 229

• Manufacturer Part Number: AT91SAM9G45-CU-999
• Description: IC MCU ARM9 APMC 324TFBGA
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM9G45-CU-999

• Core Processor: ARM9
• Core Size: 16/32-Bit
• Speed: 400MHz
• Connectivity: EBI/EMI, Ethernet, I²C, IrDA, MMC, SPI, SSC, UART/USART, USB
• Peripherals: AC'97, DMA, I²S, LCD, POR, PWM, WDT
• Number Of I /o: 160
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: ROM
• Ram Size: 128K x 8
• Voltage - Supply (vcc/vdd): 0.9 V ~ 1.1 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 324-TFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed

22. DDR/SDR SDRAM Controller (DDRSDRC)
22.1
6438F–ATARM–21-Jun-10
Description
The DDR/SDR SDRAM Controller (DDRSDRC) is a multiport memory controller. It comprises
four slave AHB interfaces. All simultaneous accesses (four independent AHB ports) are inter-
leaved to maximize memory bandwidth and minimize transaction latency due to SDRAM
protocol.The DDRSDRC supports a read or write burst length of 8 locations which frees the
command and address bus to anticipate the next command, thus reducing latency imposed by
the SDRAM protocol and improving the SDRAM bandwidth. Moreover it keeps track of the active
row in each bank, thus maximizing SDRAM performance, e.g., the application may be placed in
one bank and data in the other banks. So as to optimize performance, it is advisable to avoid
accessing different rows in the same bank. The DDRSDRC supports a CAS latency of 2 or 3 and
optimizes the read access depending on the frequency.
The features of self refresh, power-down and deep power-down modes minimize the consump-
tion of the SDRAM device.
The DDRSDRC user interface is compliant with ARM Advanced Peripheral Bus (APB rev2).
Note: The term “SDRAM device” regroups SDR-SDRAM, Mobile SDR-SDRAM, Mobile DDR1-
SDRAM and DDR2-SDRAM devices.
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