46DR83200A Datasheet, PDF (36/48 Pages) Integrated Silicon Solution, Inc – 32Mx8, 16Mx16 DDR2 DRAM

IS43/46DR83200A, IS43/46DR16160A
Burst mode operation
Burst mode operation is used to provide a constant flow of data to memory locations (write cycle), or from memory
locations (read cycle). The parameters that define how the burst mode will operate are burst sequence and burst
length. DDR2 SDRAM supports 4 bit burst and 8 bit burst modes only. For 8 bit burst mode, full interleave address
ordering is supported, however, sequential address ordering is nibble based for ease of implementation. The burst
type, either sequential or interleaved, is programmable and defined by MR[A3], which is similar to the DDR SDRAM
operation. Seamless burst read or write operations are supported. Unlike DDR devices, interruption of a burst read or
write cycle during BL = 4 mode operation is prohibited. However in case of BL = 8 mode, interruption of a burst read or
write operation is limited to two cases, reads interrupted by a read, or writes interrupted by a write. Therefore the Burst
Stop command is not supported on DDR2 SDRAM devices.
Burst Length and Sequence
Burst Length Starting Address (A1, A0)
4
00
01
10
11
Sequential Addressing (decimal)
0, 1, 2, 3
1, 2, 3, 0
2, 3, 0, 1
3, 0, 1, 2
Interleave Addressing (decimal)
0, 1, 2, 3
1, 0, 3, 2
2, 3, 0, 1
3, 2, 1, 0
Burst Length
8
Starting Address (A2, A1, A0)
000
001
010
011
100
101
110
111
Sequential Addressing (decimal)
0, 1, 2, 3, 4, 5, 6, 7
1, 2, 3, 0, 5, 6, 7, 4
2, 3, 0, 1, 6, 7, 4, 5
3, 0, 1, 2, 7, 4, 5, 6
4, 5, 6, 7, 0, 1, 2, 3
5, 6, 7, 4, 1, 2, 3, 0
6, 7, 4, 5, 2, 3, 0, 1
7, 4, 5, 6, 3, 0, 1, 2
Interleave Addressing (decimal)
0, 1, 2, 3, 4, 5, 6, 7
1, 0, 3, 2, 5, 4, 7, 6
2, 3, 0, 1, 6, 7, 4, 5
3, 2, 1, 0, 7, 6, 5, 4
4, 5, 6, 7, 0, 1, 2, 3
5, 4, 7, 6, 1, 0, 3, 2
6, 7, 4, 5, 2, 3, 0, 1
7, 6, 5, 4, 3, 2, 1, 0
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Integrated Silicon Solution, Inc. — www.issi.com
Rev. D
08/16/2012