K4T1G044QF Datasheet, PDF (36/46 Pages) Samsung semiconductor – 1Gb F-die DDR2 SDRAM

K4T1G044QF
K4T1G084QF
K4T1G164QF
datasheet
Rev. 1.11
DDR2 SDRAM
[ Table 5 ] Derating values for DDR2-667, DDR2-800
∆tIS and ∆tIH Derating Values for DDR2-667, DDR2-800
CK, CK Differential Slew Rate
2.0 V/ns
∆tIS
∆tIH
1.5 V/ns
∆tIS
∆tIH
1.0 V/ns
∆tIS
∆tIH
Units
NOTE
4.0
+150
+94
+180
+124
+210
+154
ps
1
3.5
+143
+89
+173
+119
+203
+149
ps
1
3.0
+133
+83
+163
+113
+193
+143
ps
1
2.5
+120
+75
+150
+105
+180
+135
ps
1
2.0
+100
+45
+130
+75
+160
+105
ps
1
1.5
+67
+21
+97
+51
+127
+81
ps
1
1.0
0
0
+30
+30
+60
+60
ps
1
0.9
-5
-14
+25
+16
+55
+46
ps
1
Command/
0.8
-13
-31
+17
-1
+47
+29
ps
1
Address Slew
rate(V/ns)
0.7
-22
-54
+8
-24
+38
+6
ps
1
0.6
-34
-83
-4
-53
+26
-23
ps
1
0.5
-60
-125
-30
-95
0
-65
ps
1
0.4
-100
-188
-70
-158
-40
-128
ps
1
0.3
-168
-292
-138
-262
-108
-232
ps
1
0.25
-200
-375
-170
-345
-140
-315
ps
1
0.2
-325
-500
-295
-470
-265
-440
ps
1
0.15
-517
-708
-487
-678
-457
-648
ps
1
0.1
-1000
-1125
-970
-1095
-940
-1065
ps
1
For all input signals the total tIS (setup time) and tIH (hold time) required is calculated by adding the data sheet tIS(base) and tIH(base) value to the ∆tIS
and ∆tIH derating value respectively. Example: tIS (total setup time) = tIS(base) + ∆tIS
Setup (tIS) nominal slew rate for a rising signal is defined as the slew rate between the last crossing of V_REF(DC) and the first crossing of V_IH(AC)min.
Setup (tIS) nominal slew rate for a falling signal is defined as the slew rate between the last crossing of V_REF(DC) and the first crossing of V_IL(AC)max. If
the actual signal is always earlier than the nominal slew rate line between shaded ’V_REF(DC) to ac region’, use nominal slew rate for derating value (see
Figure 15). If the actual signal is later than the nominal slew rate line anywhere between shaded ’V_REF(DC) to ac region’, the slew rate of a tangent line to
the actual signal from the ac level to dc level is used for derating value (see Figure 16).
Hold (tIH) nominal slew rate for a rising signal is defined as the slew rate between the last crossing of V_IL(DC)max and the first crossing of V_REF(DC).
Hold (tIH) nominal slew rate for a falling signal is defined as the slew rate between the last crossing of V_IH(DC)min and the first crossing of V_REF(DC). If
the actual signal is always later than the nominal slewrate line between shaded ’dc to V_REF(DC) region’, use nominal slew rate for derating value (see Fig-
ure 17). If the actual signal is earlier than the nominal slew rate line anywhere between shaded ’dc to V_REF(DC) region’, the slew rate of a tangent line to
the actual signal from the dc level to V_REF(DC) level is used for derating value (see Figure 18).
Although for slow slew rates the total setup time might be negative (i.e. a valid input signal will not have reached V_IH/IL(AC) at the time of the rising clock
transition) a valid input signal is still required to complete the transition and reach V_IH/IL(AC).
For slew rates in between the values listed in Table 4 and Table 5 the derating values may obtained by linear interpolation.
These values are typically not subject to production test. They are verified by design and characterization.
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