k4t51043qb-gce6 Samsung Semiconductor, Inc., k4t51043qb-gce6 Datasheet - Page 26

• Manufacturer Part Number: k4t51043qb-gce6
• Description: 512mb B-die Ddr2 Sdram
• Manufacturer: Samsung Semiconductor, Inc.

512Mb B-die DDR2 SDRAM
DDR2 SDRAM Default Output Driver V–I Characteristics
DDR2 SDRAM output driver characteristics are defined for full strength default operation as selected by
the EMRS1 bits A7-A9 = ‘111’. Figures 1 and 2 show the driver characteristics graphically, and tables 1 and
2 show the same data in tabular format suitable for input into simulation tools. The driver characteristics
evaluation conditions are:
Nominal Default 25
Minimum TBD
Maximum 0
Default Output Driver Characteristic Curves Notes:
1) The full variation in driver current from minimum to maximum process, temperature, and voltage will
lie within the outer bounding lines of the V–I curve of figures 1 and 2.
2) It is recommended that the ”typical” IBIS V–I curve lie within the inner bounding lines of the V–I curves
of figures 1 and 2.
Table 3. Full Strength Calibrated Pulldown Driver Characteristics
Table 4. Full Strength Calibrated Pullup Driver Characteristics
DDR2 SDRAM Calibrated Output Driver V–I Characteristics
DDR2 SDRAM output driver characteristics are defined for full strength calibrated operation as selected by
the procedure outlined in section 2.2.2.3, Off-Chip Driver (OCD) Impedance Adjustment. Tables 3 and 4
show the data in tabular format suitable for input into simulation tools. The nominal points represent a
device at exactly 18 ohms. The nominal low and nominal high values represent the range that can be
achieved with a maximum 1.5 ohm step size with no calibration error at the exact nominal conditions only
(i.e. perfect calibration procedure, 1.5 ohm maximum step size guaranteed by specification). Real system
calibration error needs to be added to these values. It must be understood that these V-I curves as repre-
sented here or in supplier IBIS models need to be adjusted to a wider range as a result of any system cali-
bration error. Since this is a system specific phenomena, it cannot be quantified here. The values in the
calibrated tables represent just the DRAM portion of uncertainty while looking at one DQ only. If the cali
Voltage (V)
Voltage (V)
0.2
0.3
0.4
0.2
0.3
0.4
o
C (T case), VDDQ = 1.9 V, fast–fast process
o
C (T case), VDDQ = 1.7 V, slow–slow process
Nominal Minimum
Nominal Minimum
o
C (T case), VDDQ = 1.8 V, typical process
(21 ohms)
(21 ohms)
14.3
18.7
-14.3
-18.7
9.5
-9.5
Nominal Low (18.75
Nominal Low (18.75
ohms)
10.7
16.0
21.0
ohms)
-10.7
-16.0
-21.0
Calibrated Pulldow n Current (mA)
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Calibrated Pullup Current (mA)
Nominal (18 ohms)
Nominal (18 ohms)
11.5
16.6
21.6
-11.4
-16.5
-21.2
Nominal High (17.25
Nominal High (17.25
ohms)
ohms)
-11.8
-17.4
-23.0
11.8
17.4
23.0
Nominal Maximum (15
Nominal Maximum (15
Rev. 0.91 (Sep. 2003)
DDR2 SDRAM
ohms)
Preliminary
-13.3
-20.0
-27.0
ohms)
13.3
20.0
27.0