EDJ1108BABG, EDJ1116BABG
Output Driver Impedance
RON will be achieved by the DDR3 SDRAM after proper I/O calibration. Tolerance and linearity requirements are
referred to the Output Driver DC Electrical Characteristics table.
A functional representation of the output buffer is shown in the figure Output Driver: Definition of Voltages and
Currents.
RON is defined by the value of the external reference resistor RZQ as follows:
• RON40 = RZQ/6
• RON34 = RZQ/7
The individual pull-up and pull-down resistors (RONPu and RONPd) are defined as follows:
Parameter
Symbol
RONPu
Definition
Conditions
VDDQ − VOUT
Output driver pull-up impedance
RONPd is turned off
IOUT
VOUT
IOUT
Output driver pull-down impedance
RONPd
RONPu is turned off
Chip in Drive Mode
Output Driver
VDDQ
IPu
To
other
circuitry
like
RCV,
...
RONPu
DQ
IOut
RONPd
IPd
VOut
VSSQ
Output Driver: Definition of Voltages and Currents
Data Sheet E1248E40 (Ver. 4.0)
24
ELPIDA [ ELPIDA MEMORY ]
