W631GG6KB-15 Datasheet, PDF (112/158 Pages) Winbond – Double Data Rate architecture: two data transfers per clock cycle

W631GG6KB
9.9 On-Die Termination (ODT) Levels and Characteristics
9.9.1 ODT Levels and I-V Characteristics
On-Die Termination effective resistance RTT is defined by bits A9, A6 and A2 of the MR1 Register.
ODT is applied to the DQ, DM and DQS/DQS# pins.
A functional representation of the on-die termination is shown in Figure 97. The individual pull-up and
pull-down resistors (RTT_Pu and RTT_Pd) are defined as follows:
RTT_Pu = ^{VDDQ - VOut}
I _Out
under the condition that RTT_Pd is turned off
RTT_Pd =
V_Out
I _Out
under the condition that RTT_Pu is turned off
Chip in Termination Mode
ODT
Ipu
VDDQ
RTTpu
Iout = IPd - IPu
To other
circuitry
like RCV, ...
RTTpd
Ipd
DQ
Iout
Vout
VSSQ
Figure 97 – On-Die Termination: Definition of Voltages and Currents
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Publication Release Date: Feb. 27, 2013
Revision A04