User Manual

34 QPHY-DDR2-OM-E Rev A
QPHY-DDR2 LIMIT SETS
DDR2-400
This corresponds to the JEDEC JESD79-2E DDR2 standard specification limits for 400 MT/s.
DDR2-533
This corresponds to the JEDEC JESD79-2E DDR2 standard specification limits for 533 MT/s.
DDR2-667
This corresponds to the JEDEC JESD79-2E DDR2 standard specification limits for 667 MT/s.
DDR2-800
This corresponds to the JEDEC JESD79-2E DDR2 standard specification limits for 800 MT/s.
DDR2-1066
This corresponds to the JEDEC JESD208 DDR2 standard specification limits for 1066 MT/s.
QPHY-DDR2 TESTS
Clock Tests
All time measure on clock CK are done at level VREF.
tCK(avg), Average Clock Period
tCK(avg) is defined as the average clock period over any 200 consecutive clock periods.
tCK(avg) = SUM(tCKi) / 200 where i=1 to 200
Measured on both the rising and the falling edge.
tCK(abs), Absolute Clock Period
tCK(abs) is defined as the absolute clock period of each of 200 consecutive clock periods.
Measured on both the rising and the falling edge.