Rev. 0.8 / Oct. 2007

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17. ODT turn off time min is when the device starts to turn off ODT resistance.

ODT turn off time max is when the bus is in high impedance. Both are measured from tAOFD.

18. tHZ and tLZ transitions occur in the same access time as valid data transitions. Thesed parameters are referenced

to a specific voltage level which specifies when the device output is no longer driving(tHZ), or begins driving (tLZ).

Below figure shows a method to calculate the point when device is no longer driving (tHZ), or begins driving (tLZ)

by measuring the signal at two different voltages. The actual voltage measurement points are not critical as long as

the calculation is consistenet.

19. tRPST end point and tRPRE begin point are not referenced to a specific voltage level but specify when the device

output is no longer driving (tRPST), or begins driving (tRPRE). Below figure shows a method to calculate these

points when the device is no longer driving (tRPST), or begins driving (tRPRE). Below Figure shows a method to

calculate these points when the device is no longer driving (tRPST), or begins driving (tRPRE) by measuring the

signal at two different voltages. The actual voltage measurement points are not critical as long as the calculation is

consistent.

20. Input waveform timing with differential data strobe enabled MR[bit10] =0, is referenced from the input signal

test.

21. Input waveform timing with differential data strobe enabled MR[bit10]=0, is referenced from the input signal

differential data strobe crosspoint for a falling signal applied to the device under test.

signal applied to the device under test.

signal applied to the device under test.

tHZ , tRPST end point = 2*T1-T2

tLZ , tRPRE begin point = 2*T1-T2

VOH + xmV

VOH + 2xmV

VOL + 1xmV

VOL + 2xmV

tHZ

tRPST end point

VTT + 2xmV

VTT + xmV

VTT -xmV

VTT - 2xmV

tHZ

tRPRE begin point

DQS

tDH

tDS

DQS

tDH

tDS

Differential Input waveform timing