hy5ps1g821m Hynix Semiconductor, hy5ps1g821m Datasheet - Page 21

• Manufacturer Part Number: hy5ps1g821m
• Description: 1gb Ddr2 Sdram
• Manufacturer: Hynix Semiconductor

Rev. 0.2 / Oct. 2005
2.3.2.4 ODT (On Die Termination)
On Die Termination (ODT) is a feature that allows a DRAM to turn on/off termination resistance for each DQ,
DQS/DQS, RDQS/RDQS, and DM signal for x4x8 configurations via the ODT control pin. For x16 configura-
tion ODT is applied to each DQ, UDQS/UDQS, LDQS/LDQS, UDM, and LDM signal via the ODT control pin.
The ODT feature is designed to improve signal integrity of the memory channel by allowing the DRAM con-
troller to independently turn on/off termination resistance for any or all DRAM devices.
The ODT function is supported for ACTIVE and STANDBY modes. ODT is turned off and not supported in
SELF REFRESH mode.
FUNCTIONAL REPRESENTATION OF ODT
Target Rtt (ohm) = (Rval1) / 2 or (Rval2) / 2
Selection between sw1 or sw2 is determined by “Rtt (nominal)” in EMRS
Switch sw1 or sw2 is enabled by ODT pin.
Termination included on all DQs, DM, DQS, DQS, RDQS, and RDQS pins.
DRAM
Buffer
Input
V
V
SS
DD
Q
Q
sw1
sw1
Rval1
Rval1
V
V
DD
SS
Q
Q
sw2
sw2
Rval2
Rval2
Input
Pin
1HY5PS12421(L)M
HY5PS12821(L)M
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