EDJ1108BABG, EDJ1116BABG
tLZ (DQS), tLZ (DQ), tHZ (DQS), tHZ (DQ) Notes
tHZ and tLZ transitions occur in the same access time as valid data transitions. These parameters are referenced to
a specific voltage level which specifies when the device output is no longer driving tHZ(DQS) and tHZ(DQ), or begins
driving tLZ(DQS), tLZ(DQ). The figure below shows a method to calculate the point when device is no longer driving
tHZ(DQS) and tHZ(DQ), or begins driving tLZ(DQS), tLZ(DQ) by measuring the signal at two different voltages. The
actual voltage measurement points are not critical as long as the calculation is consistent. The parameters
tLZ(DQS), tLZ(DQ), tHZ(DQS), and tHZ(DQ) are defined as singled ended.
tLZ (DQS): CK-/CK rising crossing at RL-1
tLZ (DQ): CK-/CK rising crossing at RL
tHZ (DQS), tHZ (DQ) with BL8: CK-/CK rising crossing at RL + 4nCK
tHZ (DQS), tHZ (DQ) with BL4: CK-/CK rising crossing at RL + 2nCK
VTT + 2x mV
VOH − x mV
VOH − 2x mV
VTT + x mV
tLZ (DQS), tLZ (DQ)
tHZ (DQS), tHZ (DQ)
VTT − x mV
VOL + 2x mV
T1
T2
VTT − 2x mV
VOL + x mV
T2
T1
tLZ (DQS), tLZ (DQ) begin point = 2 T1 - T2
tHZ (DQS), tHZ (DQ) end point = 2 T1 - T2
Method for Calculating Transitions and Endpoints
Data Sheet E1248E40 (Ver. 4.0)
101
ELPIDA [ ELPIDA MEMORY ]
