MT41J128M8 MDTIC [Micon Design Technology Corporation], MT41J128M8 Datasheet - Page 54

• Manufacturer Part Number: MT41J128M8
• Description: 1Gb: x4, x8, x16 DDR3 SDRAM
• Manufacturer: MDTIC [Micon Design Technology Corporation]

Output Driver Impedance
Figure 29: Output Driver
34Ω Output Driver Impedance
PDF: 09005aef826aa906/Source: 09005aef82a357c3
1Gb_DDR3_3.fm - Rev. D 8/1/08 EN
The output driver impedance is selected by MR1[5,1] during initialization. The selected
value is able to maintain the tight tolerances specified if proper ZQ calibration is
performed. Output specifications refer to the default output driver unless specifically
stated otherwise. A functional representation of the output buffer is shown in Figure 29
on page 54. The output driver impedance R
reference resistor RZQ as follows:
• R
The individual pull-up and pull-down resistors (R
follows:
• R
• R
The 34Ω driver (MR1[5, 1] = 01) is the default driver. Unless otherwise stated, all timings
and specifications listed herein apply to the 34Ω driver only. Its impedance R
defined by the value of the external reference resistor RZQ as follows: R
(with nominal RZQ = 240Ω
driver impedance characteristics are listed in Table 35 on page 55.
tively)
ON x
ON PU
ON PD
To
other
circuitry
such as
RCV, . . .
= RZQ/y (with RZQ = 240Ω
= (V
= (V
Chip in drive mode
OUT
DD
Output driver
R
R
Q - V
ON PU
ON PD
)/|I
I
I
PU
PD
OUT
OUT
|, when R
)/|I
±
OUT
1 percent) and is actually 34.3Ω
54
|, when R
ON PU
±
1 percent; x = 34Ω or 40Ω with y = 7 or 6, respec-
I
OUT
Micron Technology, Inc., reserves the right to change products or specifications without notice.
is turned off
ON PD
ON
V
DQ
V
V
is defined by the value of the external
is turned off
DD
OUT
SS
1Gb: x4, x8, x16 DDR3 SDRAM
Q
Q
ON PU
Output Driver Impedance
and R
±
ON PD
1 percent. The 34Ω output
©2006 Micron Technology, Inc. All rights reserved.
) are defined as
ON 34
= RZQ/7
ON
is