HYB18T512xxxBF–[2.5…5]
512-Mbit Double-Data-Rate-Two SDRAM
5.3
DC & AC Characteristics
DDR2 SDRAM pin timing are specified for either single relative to the rising or falling edges of DQS crossing at
ended or differential mode depending on the setting of REF. In differential mode, these timing relationships
V
the EMRS(1) “Enable DQS” mode bit; timing are measured relative to the crosspoint of DQS and its
advantages of differential mode are realized in system complement, DQS. This distinction in timing methods is
design. The method by which the DDR2 SDRAM pin verified by design and characterization but not subject
timing are measured is mode dependent. In single to production test. In single ended mode, the DQS (and
ended mode, timing relationships are measured RDQS) signals are internally disabled and don’t care.
Table 24
Symbol
DC & AC Logic Input Levels for DDR2-667 and DDR2-800
Parameter
DDR2-667, DDR2-800
Min.
Units
Max.
VIH(dc)
VIL(dc)
VIH(ac)
VIL(ac)
DC input logic high
DC input low
V
REF + 0.125
V
V
DDQ + 0.3
REF – 0.125
V
V
V
V
–0.3
AC input logic high
AC input low
V
REF + 0.200
—
—
VREF – 0.200
Table 25
Symbol
DC & AC Logic Input Levels for DDR2-533 and DDR2-400
Parameter
DDR2-533, DDR2-400
Min.
Units
Max.
VIH(dc)
VIL(dc)
VIH(ac)
VIL(ac)
DC input logic high
DC input low
V
REF + 0.125
V
V
DDQ + 0.3
V
V
V
V
–0.3
REF - 0.125
AC input logic high
AC input low
V
REF + 0.250
—
—
VREF - 0.250
Table 26
Symbol
VREF
Single-ended AC Input Test Conditions
Condition
Value
Unit
V
Note
1)
Input reference voltage
0.5 x VDDQ
1.0
VSWING.MAX
SLEW
Input signal maximum peak to peak swing
Input signal minimum Slew Rate
V
—
2)3)
1.0
V / ns
1) Input waveform timing is referenced to the input signal crossing through the VREF level applied to the device under test.
2) The input signal minimum Slew Rate is to be maintained over the range from VIH(ac).MIN to VREF for rising edges and the
range from VREF to VIL(ac).MAX for falling edges as shown in Figure 4
3) AC timings are referenced with input waveforms switching from VIL(ac) to VIH(ac) on the positive transitions and VIH(ac) to VIL(ac)
on the negative transitions.
Internet Data Sheet
27
Rev. 1.05, 2007-01
03292006-YBYM-WG0Z
QIMONDA [ QIMONDA AG ]
