HY5PS561621BLFPE3 Datasheet, PDF (11/34 Pages) Hynix Semiconductor – 256Mb DDR2 SDRAM

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1HY5PS561621B(L)FP
3.2.4 Differential Input AC logic Level
Symbol
Parameter
Min.
Max.
Units Notes
V_ID (ac)
V_IX (ac)
ac differential input voltage
ac differential cross point voltage
0.5
VDDQ + 0.6
V
1
0.5 * VDDQ - 0.175
0.5 * VDDQ + 0.175
V
2
1. VIN(DC) specifies the allowable DC execution of each input of differential pair such as CK, CK, DQS, DQS, LDQS, LDQS, UDQS
and UDQS.
2. VID(DC) specifies the input differential voltage |VTR -VCP | required for switching, where VTR is the true input (such as CK,
DQS, LDQS or UDQS) level and VCP is the complementary input (such as CK, DQS, LDQS or UDQS) level. The minimum value
is equal to VIH(DC) - V IL(DC).
V_TR
V_CP
V_DDQ
V_ID
Crossing point
V_{IX or} V_OX
V_SSQ
< Differential signal levels >
Note:
1. VID(AC) specifies the input differential voltage |VTR -VCP | required for switching, where VTR is the true input signal (such as
CK, DQS, LDQS or UDQS) and VCP is the complementary input signal (such as CK, DQS, LDQS or UDQS). The minimum value
is equal to V IH(AC) - V IL(AC).
2. The typical value of VIX(AC) is expected to be about 0.5 * VDDQ of the transmitting device and VIX(AC) is expected to track
variations in VDDQ . VIX(AC) indicates the voltage at which differential input signals must cross.
3.2.5 Differential AC output parameters
Symbol
Parameter
Min.
Max.
Units Notes
V_OX (ac)
ac differential cross point voltage
0.5 * VDDQ - 0.125 0.5 * VDDQ + 0.125
V
1
Note:
1. The typical value of VOX(AC) is expected to be about 0.5 * V DDQ of the transmitting device and VOX(AC) is expected to track
variations in VDDQ . VOX(AC) indicates the voltage at whitch differential output signals must cross.
Rev. 0.2 / Apr. 2008
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