HYB18M1G16 Datasheet, PDF (57/65 Pages) Qimonda AG – 1-Gbit x16 DDR Mobile-RAM

Data Sheet
HY[B/E]18M1G16[0/1]BF
1-Gbit DDR Mobile-RAM
19) The maximum limit for this parameter is not a device limit. The device operates with a greater value for this parameter, but system
performance (bus turnaround) will degrade accordingly.
20) A low level on DQS may be maintained during High-Z states (DQS drivers disabled) by adding a weak pull-down element in the system. It
is recommended to turn off the weak pull-down element during read and write bursts (DQS drivers enabled).
21) These parameters account for the number of clock cycles and depend on the operating frequency, as follows:
no. of clock cycles = specified delay / clock period; round to the next higher integer.
22) t_DAL = (t_WR / t_CK) + (t_RP / t_CK): for each of the terms above, if not already an integer, round to the next higher integer.
23) A maximum of eight AUTOREFRESH commands can be posted to the DDR Mobile-RAM device, meaning that the maximum absolute
interval between any Refresh command and the next Refresh command is 8 * t_REFI.
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FIGURE 40
Measurement with Reference Load
TABLE 24
Output Slew Rate Characteristics
Parameter
Typical Range
Minimum
Maximum Unit Note
Pull-up and Pull-down Slew Rate
(Full Drive Buffer)
TBD
0.7
2.5
V/ns ¹⁾²⁾
Pull-up and Pull-down Slew Rate
(Half Drive Buffer)
TBD
0.3
1.0
V/ns ¹⁾²⁾
Output Slew Rate Matching Ratio
(Pull-up to Pull-down)
-
0.7
1.4
-
1)3)
1) Output slew rate is measured between V_ILD(DC) and V_IHD(AC) (rising) or V_IHD(DC) and V_ILD(AC) (falling).
2) The parameter is measured using a 20pF capacitive load connected to V_SSQ.
3) The ratio of the pull-up slew rate to the pull-down slew rate is specified for the same temperature and voltage, over the entire temperature
and voltage range. For a given output, it represents the maximum difference between pull-up and pull-down drivers due to process
variation.
Parameter
Maximum peak amplitude allowed for overshoot
Maximum peak amplitude allowed for undershoot
Maximum overshoot area above V_DD
Maximum undershoot area below V_SS
TABLE 25
AC Overshoot / Undershoot Specification
Maximum Unit Note
0.9
V
–
0.9
V
–
3.0
V-ns –
3.0
V-ns –
Rev.1.0, 2007-03
57
10242006-Y557-TZXW