IBMN625404GT3B
IBMN625804GT3B
Preliminary
256Mb Double Data Rate Synchronous DRAM
AC Characteristics
(Notes 1-5 apply to the following Tables; Electrical Characteristics and DC Operating Conditions, AC Operating
Conditions, IDD Specifications and Conditions, and Electrical Characteristics and AC Timing.)
1. All voltages referenced to VSS
.
2. Tests for AC timing, IDD, and electrical, AC and DC characteristics, may be conducted at nominal reference/supply
voltage levels, but the related specifications and device operation are guaranteed for the full voltage range specified.
3. Outputs measured with equivalent load. Refer to the AC Output Load Circuit below.
4. AC timing and IDD tests may use a VIL to VIH swing of up to 1.5V in the test environment, but input timing is still refer-
enced to VREF (or to the crossing point for CK, CK), and parameter specifications are guaranteed for the specified AC
input levels under normal use conditions. The minimum slew rate for the input signals is 1V/ns in the range between
VIL(AC) and VIH(AC).
5. The AC and DC input level specifications are as defined in the SSTL_2 Standard (i.e. the receiver effectively
switches as a result of the signal crossing the AC input level, and remains in that state as long as the signal does not
ring back above (below) the DC input low (high) level.
AC Output Load Circuit Diagrams
V
V
DDQ
TT
50Ω
150Ω
Output
(V
QFC
(V
Timing Reference Point
Timing Reference Point
)
)
OUT
OUT
30pF
15pF
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
29L0011.E36997B
1/01
Page 57 of 79