HY5PS56421LF-E3 Datasheet, PDF (13/35 Pages) Hynix Semiconductor – 256Mb DDR2 SDRAM

HY5PS56421(L)F
HY5PS56821(L)F
HY5PS561621(L)F
3.2.4 Differential Input AC logic Level
Symbol
V_ID (ac)
V_IX (ac)
Parameter
ac differential input voltage
ac differential cross point voltage
Min.
0.5
0.5 * VDDQ - 0.175
Max.
VDDQ + 0.6
0.5 * VDDQ + 0.175
Units
V
V
Notes
1
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_DDQ
V_TR
V_CP
V_ID
Crossing point
V_{IX or} V_OX
V_SSQ
< Differential signal levels >
Notes:
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
V_OX (ac)
Parameter
ac differential cross point voltage
Min.
0.5 * VDDQ - 0.125
Max.
0.5 * VDDQ + 0.125
Units
V
Notes
1
Notes:
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 1.0/July. 2004
13