Datasheet

Rev. 1.1 / May. 2013 31
AC and DC Input Levels for Single-Ended Signals
DDR3 SDRAM will support two Vih/Vil AC levels for DDR3-800 and DDR3-1066 as specified in the table
below. DDR3 SDRAM will also support corresponding tDS values (Table 43 and Table 51 in “ DDR3 Device
Operation”) as well as derating tables in Table 46 of “DDR3 Device Operation” depending on Vih/Vil AC lev-
els.
Notes:
1. Vref = VrefDQ (DC).
2. Refer to "Overshoot and Undershoot Specifications" on page 43.
3. The ac peak noise on V
Ref
may not allow V
Ref
to deviate from V
RefDQ(DC)
by more than +/-1% VDD (for reference:
approx. +/- 15 mV).
4. For reference: approx. VDD/2 +/- 15 mV.
5. VIH(dc) is used as a simplified symbol for VIH.DQ(DC100)
6. VIL(dc) is used as a simplified symbol for VIL.DQ(DC100)
7. VIH(ac) is used as simplified symbol for VIH.DQ(AC175), VIH.DQ(AC150), and VIH.DQ(AC135); VIH.DQ(AC175)
value is used when Vref + 0.175V is referenced, VIH.DQ(AC150) value is used when Vref + 0.150V is referenced,
and VIH.DQ(AC135) value is used when Vref + 0.135V is referenced.
8. VIL(ac) is used as simplified symbol for VIL.DQ(AC175), VIL.DQ(AC150), and VIL.DQ(AC135); VIL.DQ(AC175)
value is used when Vref - 0.175V is referenced, VIL.DQ(AC150) value is used when Vref - 0.150V is referenced,
and VIL.DQ(AC135) value is used when Vref - 0.135V is referenced.
Single Ended AC and DC Input Levels for DQ and DM
Symbol Parameter
DDR3-800/1066 DDR3-1333/1600 DDR3-1866
Unit Notes
Min Max Min Max Min Max
VIH.DQ(DC100) DC input logic high Vref + 0.100 VDD Vref + 0.100 VDD Vref + 0.100 VDD V 1, 5
VIL.DQ(DC100) DC input logic low VSS Vref - 0.100 VSS Vref - 0.100 VSS Vref - 0.100 V 1, 6
VIH.DQ(AC175) AC input logic high Vref + 0.175 Note2 - - - - V 1, 2, 7
VIL.DQ(AC175) AC input logic low Note2 Vref - 0.175 - - - - V 1, 2, 8
VIH.DQ(AC150) AC Input logic high Vref + 0.150 Note2 Vref + 0.150 Note2 Vref + 0.150 Note2 V 1, 2, 7
VIL.DQ(AC150) AC input logic low Note2 Vref - 0.150 Note2 Vref - 0.150 Note2 Vref - 0.150 V 1, 2, 8
VIH.CA(AC135)AC input logic high----Vref + 0.135Note2mV1, 2, 7
VIL.CA(AC135) AC input logic low ----Note2Vref - 0.135mV1, 2, 8
V
RefDQ(DC
)
Reference Voltage
for DQ, DM inputs
0.49 * VDD 0.51 * VDD 0.49 * VDD 0.51 * VDD 0.49 * VDD 0.51 * VDD V 3, 4