HYB18T1G[40/80/16]0AF(L)–[3S/3.7/5]
1-Gbit DDR2 SDRAM
Timing Characteristics
7
Timing Characteristics
7.1
Speed Grade Definitions
Table 34
Speed Grade Definition Speed Bins for DDR2–667D
Speed Grade
DDR2–667D
–3S
Unit
Note
IFX Sort Name
CAS-RCD-RP latencies
Parameter
5–5–5
tCK
—
ns
ns
ns
ns
ns
ns
ns
Symbol
tCK
Min.
5
Max.
1)2)3)4)
1)2)3)4)
1)2)3)4)
1)2)3)4)5)
1)2)3)4)
1)2)3)4)
1)2)3)4)
Clock Frequency
@ CL = 3
@ CL = 4
@ CL = 5
8
tCK
3.75
3
8
tCK
8
Row Active Time
Row Cycle Time
RAS-CAS-Delay
Row Precharge Time
tRAS
tRC
tRCD
tRP
45
60
15
15
70000
—
—
—
1) Timings are guaranteed with CK/CK differential Slew Rate of 2.0 V/ns. For DQS signals timings are guaranteed with a
differential Slew Rate of 2.0 V/ns in differential strobe mode and a Slew Rate of 1 V/ns in single ended mode. Timings are
further guaranteed for normal OCD drive strength (EMRS(1) A1 = 0) under the “Reference Load for Timing Measurements”
only.
2) The CK/CK input reference level (for timing reference to CK/CK) is the point at which CK and CK cross. The DQS / DQS,
RDQS / RDQS, input reference level is the crosspoint when in differential strobe mode.
3) Inputs are not recognized as valid until VREF stabilizes. During the period before VREF stabilizes, CKE = 0.2 x VDDQ is
recognized as low.
4) The output timing reference voltage level is VTT.
5) tRAS.MAX is calculated from the maximum amount of time a DDR2 device can operate without a refresh command which is
equal to 9 x tREFI
.
Internet Data Sheet
35
Rev. 1.31, 2007-01
03292006-1X3H-6X8S