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FUJITSU SEMICONDUCTOR CONFIDENTIAL
MB86R12 Application Note
DDR3 Interface PCB
Design Guideline
4.6.
ZQ/ODT setting
Table 4-3 shows the ZQ setting conditions.
Table 4-3 ZQ setting conditions
Group name
Output impedance of MB86R12 I/O (RON)
ZQ setting of MB86R12
MCK_Group
40
Ω
Perform the ZQ calibration, and set it
automatically.
MDQSx_Group
48
Ω
MDQx_Group
48
Ω
MCNTL_Group
60
Ω
MCMD_Group
60
Ω
Table 4-4 shows the recommended ODT setting conditions for MDQSx_Group and MDQx_Group signals.
Table 4-4 ODT setting conditions
Operating condition
MB86R12
DDR3_SDRAM
Write to DDR3_SDRAM
Off
60
Ω
Read from DDR3_SDRAM
40
Ω
Off