HY5PS1G421LM HYNIX [Hynix Semiconductor], HY5PS1G421LM Datasheet - Page 67

• Manufacturer Part Number: HY5PS1G421LM
• Description: 1Gb DDR2 SDRAM(DDP)
• Manufacturer: HYNIX [Hynix Semiconductor]

Rev. 0.2 / Oct. 2005
5.4.3 Calibrated Output Driver V-I Characteristics
DDR2 SDRAM output driver characteristics are defined for full strength calibrated operation as selected by
the procedure in OCD impedance adjustment. The below Tables 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 represented here or in supplier IBIS models need to be
adjusted to a wider range as a result of any system calibration error. Since this is a system specific phe-
nomena, 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 calibration procedure is used, it is possible to cause the
device to operate outside the bounds of the default device characteristics tables and figures. In such a situ-
ation, the timing parameters in the specification cannot be guaranteed. It is solely up to the system applica-
tion to ensure that the device is calibrated between the minimum and maximum default values at all times.
If this can’t be guaranteed by the system calibration procedure, re-calibration policy, and uncertainty with
DQ to DQ variation, then it is recommended that only the default values be used. The nominal maximum
and minimum values represent the change in impedance from nominal low and high as a result of voltage
and temperature change from the nominal condition to the maximum and minimum conditions. If calibrated
at an extreme condition, the amount of variation could be as much as from the nominal minimum to the
nominal maximum or vice versa. The driver characteristics evaluation conditions are:
Nominal 25
Nominal Low and Nominal High 25
Nominal Minimum TBD
Nominal Maximum 0
Full Strength Calibrated Pulldown Driver Characteristics
Full Strength Calibrated Pullup Driver Characteristics
Voltage (V)
Voltage (V)
0.2
0.3
0.4
0.2
0.3
0.4
o
C (T case), VDDQ = 1.8 V, typical process
Nominal Minimum
Nominal Minimum
(21 ohms)
o
(21 ohms)
C (T case), VDDQ = 1.9 V, any process
14.3
18.7
9.5
o
-14.3
-18.7
-9.5
C (T case), VDDQ = 1.7 V, any process
Nominal Low (18.75
Nominal Low (18.75
o
C (T case), VDDQ = 1.8 V, any process
ohms)
10.7
16.0
21.0
ohms)
-10.7
-16.0
-21.0
Calibrated Pulldow n Current (mA)
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)
11.8
17.4
23.0
ohms)
-11.8
-17.4
-23.0
1HY5PS12421(L)M
HY5PS12821(L)M
Nominal Maximum (15
Nominal Maximum (15
ohms)
ohms)
-13.3
-20.0
-27.0
13.3
20.0
27.0
67