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HYB18T1G400BF_07 Datasheet, PDF (64/74 Pages) Qimonda AG – 1-Gbit Double-Data-Rate-Two SDRAM
Internet Data Sheet
HY[B/I]18T1G[40/80/16]0B[C/F](L/V)
1-Gbit Double-Data-Rate-Two SDRAM
7.4
ODT AC Electrical Characteristics
This chapter describes the ODT AC electrical characteristics.
Symbol
TABLE 60
ODT AC Characteristics and Operating Conditions for DDR2-533 and DDR2-400
Parameter / Condition
Values
Unit
Note
Min.
Max.
tAOND
tAON
ODT turn-on delay
ODT turn-on
2
tAC.MIN
2
tAC.MAX + 1 ns
tCK
ns
1)
tAONPD
ODT turn-on (Power-Down Modes)
tAC.MIN + 2 ns 2 tCK + tAC.MAX + 1 ns
ns
tAOFD
tAOF
ODT turn-off delay
ODT turn-off
2.5
tAC.MIN
2.5
tAC.MAX + 0.6 ns
tCK
ns
2)
tAOFPD
ODT turn-off (Power-Down Modes)
tAC.MIN + 2 ns 2.5 tCK + tAC.MAX + 1 ns ns
tANPD
ODT to Power Down Mode Entry Latency
3
—
tCK
tAXPD
ODT Power Down Exit Latency
8
—
tCK
1) ODT turn on time min. is when the device leaves high impedance and ODT resistance begins to turn on. ODT turn on time max is when
the ODT resistance is fully on. Both are measured from tAOND, which is interpreted differently per speed bin. For DDR2-400/533, tAOND is
10 ns (= 2 x 5 ns) after the clock edge that registered a first ODT HIGH if tCK = 5 ns.
2) ODT turn off time min. is when the device starts to turn off ODT resistance. ODT turn off time max is when the bus is in high impedance.
Both are measured from tAOFD. Both are measured from tAOFD, which is interpreted differently per speed bin. For DDR2-400/533, tAOFD is
12.5 ns (= 2.5 x 5 ns) after the clock edge that registered a first ODT HIGH if tCK = 5 ns.
Symbol
TABLE 61
ODT AC Characteristics and Operating Conditions for DDR2-667 and DDR2-800
Parameter / Condition
Values
Unit
Note
Min.
Max.
tAOND
ODT turn-on delay
2
2
nCK
1)
tAON
ODT turn-on
tAC.MIN
tAC.MAX + 0.7 ns
ns
1)2)
tAONPD
ODT turn-on (Power-Down Modes)
tAC.MIN + 2 ns 2 tCK + tAC.MAX + 1 ns
ns
1)
tAOFD
ODT turn-off delay
2.5
2.5
nCK
1)
tAOF
ODT turn-off
tAC.MIN
tAC.MAX + 0.6 ns
ns
1)3)
tAOFPD
ODT turn-off (Power-Down Modes)
tAC.MIN + 2 ns 2.5 tCK + tAC.MAX + 1 ns ns
1)
tANPD
ODT to Power Down Mode Entry Latency
3
—
nCK
1)
tAXPD
ODT Power Down Exit Latency
8
—
nCK
1)
1) New units, “tCK.AVG” and “nCK”, are introduced in DDR2-667 and DDR2-800. Unit “tCK.AVG” represents the actual tCK.AVG of the input clock
under operation. Unit “nCK” represents one clock cycle of the input clock, counting the actual clock edges. Note that in DDR2-400 and
DDR2-533, “tCK” is used for both concepts. Example: tXP = 2 [nCK] means; if Power Down exit is registered at Tm, an Active command may
be registered at Tm + 2, even if (Tm + 2 - Tm) is 2 x tCK.AVG + tERR.2PER(Min).
2) ODT turn on time min is when the device leaves high impedance and ODT resistance begins to turn on. ODT turn on time max is when the
ODT resistance is fully on. Both are measured from tAOND, which is interpreted differently per speed bin. For DDR2-667/800, tAOND is 2 clock
cycles after the clock edge that registered a first ODT HIGH counting the actual input clock edges.
3) ODT turn off time min is when the device starts to turn off ODT resistance. ODT turn off time max is when the bus is in high impedance.
Both are measured from tAOFD, which is interpreted differently per speed bin. For DDR2-667/800, if tCK(avg) = 3 ns is assumed, tAOFD is 1.5
ns (= 0.5 x 3 ns) after the second trailing clock edge counting from the clock edge that registered a first ODT LOW and by counting the
actual input clock edges.
Rev. 1.3, 2007-07
64
03062006-ZNH8-HURV