Internet Data Sheet
HYS[64/72]T[32/64/128]xx0HU–[3/3S/3.7/5]–A
Unbuffered DDR2 SDRAM Modules
3.3
AC Characteristics
This chapter contains the AC operating conditions tables.
3.3.1
Speed Grade Definitions
List of speed grade definition tables.
•
•
•
Table 14 “Speed Grade Definition Speed Bins for DDR2–667” on Page 18
Table 15 “Speed Grade Definition Speed Bins for DDR2–533C” on Page 19
Table 16 “Speed Grade Definition Speed Bins for DDR2–400B” on Page 19
TABLE 14
Speed Grade Definition Speed Bins for DDR2–667
Speed Grade
DDR2–667C
DDR2–667D
Unit
Notes
QAG Sort Name
CAS-RCD-RP latencies
–3
–3S
4–4–4
5–5–5
tCK
Parameter
Symbol
Min.
Max.
Min.
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
tCK
5
8
5
8
ns
ns
ns
ns
ns
ns
ns
tCK
3
8
3.75
3
8
tCK
3
8
8
Row Active Time
Row Cycle Time
RAS-CAS-Delay
Row Precharge Time
tRAS
tRC
tRCD
tRP
45
57
12
12
70000
—
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) .
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) RAS.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
t
.
Rev. 1.41, 2007-05
18
03292006-EZUJ-JY4S