K4N51163QC-ZC Datasheet, PDF (29/64 Pages) Samsung semiconductor – 512Mbit gDDR2 SDRAM

K4N51163QC-ZC
512M gDDR2 SDRAM
ODT (On Die Termination)
On Die Termination (ODT) is a feature that allows a DRAM to turn on/off termination resistance. For x16 configuration 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 controller to independently turn on/off termination resistance for any or all DRAM
devices. The ODT function is supported for ACTIVE and STANDBY modes, and turned off and not supported in SELF REFRESH mode.
Functional Representation of ODT
VDDQ
sw1
VDDQ
sw2
VDDQ
sw3
Switch (sw1, sw2, sw3) is enabled by ODT pin.
Selection among sw1, sw2 and sw3 is determined by “Rtt (nominal)” in EMRS
Termination included on all DQs, DM, DQS, DQS, RDQS, and RDQS pins.
DRAM
Input
Buffer
Rval1
Rval1
Rval2
Rval2
Rval3
Rval3
Input
Pin
sw1
sw2
sw3
VSSQ
VSSQ
ODT DC Electrical Characteristics
VSSQ
Parameter/Condition
Symbol Min Nom Max Units Notes
Rtt effective impedance value for EMRS(A6,A2)=0,1; 75 ohm
Rtt1(eff) 60
75
90 ohm
1
Rtt effective impedance value for EMRS(A6,A2)=1,0; 150 ohm
Rtt2(eff) 120 150 180 ohm
1
Rtt mismatch tolerance between any pull-up/pull-down pair
Rtt(mis) -3.75
+3.75 %
1
Note 1: Test condition for Rtt measurements
Measurement Definition for Rtt(eff): Apply V_IH (AC) and V_IL (AC) to test pin separately, then measure current I(V_IH (AC)) and I( V_IL (AC)) respec-
tively. V_IH (AC), V_IL (AC), and VDDQ values defined in SSTL_18
Rtt(eff) = ^{VIH (AC) - VIL (AC)}
I(V_IH (AC)) - I(V_IL (AC))
delta VM =
2 x Vm
- 1 x 100%
V_DDQ
Measurement Definition for VM : Measure voltage (VM) at test pin (midpoint) with no load.
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Rev 1.5 Oct. 2005