6402 datasheet(26/250 Pages) INTEL

26 / 250 page

DDR Interface

Intel® 6400/6402 Advanced Memory Buffer Datasheet

3.3

Command / Address Outputs

Two sets of DRAM command and address output pins are provided for loading and

timing considerations. Each set drives the same DRAM commands, but the two address

busses are inverted from each other in order to reduce power consumption and heat

produced on the DIMM. The command and address output pin behavior is detailed

below:

1. Minimum address toggling. The address associated with the last command issued

on the DRAM bus is retained during DRAM NOP/Deselect commands. The address

and bank bits do not revert to all 1’s (or all 0’s) when the command bus is idle.

2. Balanced bank and address busses. With some exceptions, the bank and address

busses on the two bus copies are inverted from each other. This minimizes the

current load on the VTT supply regulator because the balanced address bus sinks as

much current as it sources. There are exceptions to the inversion behavior to allow

for commands that use one or more address bits to control DRAM functionality.

Balancing can also be disabled by setting the DRC.BALDIS register field.

Balancing Exceptions:

a. Address bit A10 is not balanced during all read, write, and precharge commands.

b. No address or bank bits are balanced during any MRS and EMRS commands.

c. Column address A0 is not balanced when the DRC.SEQADD bit is set. As with

A10, A0 is only not balanced during read, write, and precharge commands. This

mode is intended to work with DRAMs in sequential address mode.

d. No address or bank bits are balanced during any command when the

DRC.BALDIS register field is set.

3. Balanced idle command bus. When the command bus is idle, a deselect command

is issued with all chip selects high and all RAS/CAS/WE signals driven low on both

command/address copies.

4. Command/Address output control with CKE. All command and address pin outputs,

except for ODT, CKE, and CLK, will float one DRAM clock cycle after both CKE pins

transition from high to low. The command/address pins will be driven to valid signal

levels on the same cycle that either CKE pin is driven from low to high.

5. Output control during link reset. When the AMB core logic is in reset, CKE and ODT

will be driven low, and CLK will run at normal levels and frequency. The remaining

command/address pins will float during reset.

6. Command/Address output control in S3 mode. When the AMB core logic is in S3

power mode, all command/address outputs, including CKE, ODT, CLK, and all other

command/address pins, will be driven low.

7. CSR output control of command/address. All command/address pin outputs will

float when the appropriate DRC bits are set. Setting the DRC.CADIS field will float

the RAS, CAS, WE, Bank, and Address pins. DRC.CSDIS controls the chip select

pins. DRC.ODTDIS, DRC.CKEDIS, and DRC.CLKDIS float the ODT, CKE, and clock

pins respectively.

6402 데이터시트(PDF) 26 Page - Intel Corporation

6402 데이터시트(HTML) 26 Page - Intel Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

데이터시트 다운로드

링크 URL