Keysight Technologies D9020DDRC, Manual

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15 Data Strobe Timing (DST) Tests
226 DDR2(+LP) Compliance Testing Methods of Implementation
tDQSL, DQS Input Low Pulse Width - Test Method of Implementation
The purpose of this test is to verify that the width of the low level of the Data Strobe signal is within
the conformance limit as specified in the JEDEC specification.
Signals of Interest
Mode Supported: DDR2, LPDDR2
Signal cycle of interest: WRITE
Signal(s) of Interest:
• Data Strobe Signal (supported by Data Signal)
Optional signal(s):
• Chip Select Signal (this signal is used to separate DQ signals from different rank of memory)
Signals required to perform the test on the oscilloscope:
• Data Signal, DQ
• Data Strobe Signal, DQS
• Chip Select Signal, CS (optional)
Test Definition Notes from the Specification
Table 143 Timing Parameters by Speed Grade (DDR2-400 and DDR2-533) & (DDR2-667 and DDR2-800)
Parameter Symbol DDR2-400 DDR2-533 Units Specific
Notes
Min Max Min Max
DQS input LOW pulse width tDQSL 0.35 x 0.35 x tCK
Parameter Symbol DDR2-667 DDR2-800 Units Specific
Notes
Min Max Min Max
DQS input LOW pulse width tDQSL 0.35 x 0.35 x tCK(avg)
Table 144 Timing Parameters by Speed Grade (DDR2-1066)
Parameter Symbol DDR2-1066 Units Specific
Notes
Min Max
DQS input LOW pulse width tDQSL 0.35 x tCK(avg)
Table 145 LPDDR2 AC Timing Table
Parameter Symbol Min
Max Min
t
CK
LPDDR2 Unit
1066 933 800 677 533 466*
5
400 333 266*
5
200*
5
Write Parameters*
14
DQS input low
level width
tDQSL Min
0.4 tCK(avg)