W632GU6NB
Publication Release Date: Aug. 20, 2018
Revision: A01
- 115 -
10.9.4 Design guide lines for R
TT
PU
and R
TT
PD
Table 35 provides an overview of the ODT DC electrical pull-up and pull-down characteristics. The
values are not specification requirements, but can be used as design guide lines.
Table 35
– ODT DC Electrical Pull-Down and Pull-Up Characteristics, assuming R
ZQ
= 240 Ω ± 1%
entire operating temperature range; after proper ZQ calibration
MR1 A9, A6, A2
R
TT
Resistor
V
out
Min. Nom. Max.
Unit
Notes
0, 1, 0
120 Ω, R
TT
120PD240
,
V
OLDC
= 0.2 × V
DDQ
0.6
1.0
1.15 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
0, 0, 1
60 Ω, R
TT
60PD120
,
V
OMDC
= 0.5 × V
DDQ
0.9
1.0
1.15 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
0, 1, 1
40 Ω, R
TT
40PD80
,
V
OHDC
= 0.8 × V
DDQ
0.9
1.0
1.45 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
1, 0, 1
30 Ω, R
TT
30PD60
,
1, 0, 0
20 Ω R
TT
20PD40
R
TT
120PU240
,
V
OLDC
= 0.2 × V
DDQ
0.9
1.0
1.45 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
R
TT
60PU120
,
V
OMDC
= 0.5 × V
DDQ
0.9
1.0
1.15 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
R
TT
40PU80
,
V
OHDC
= 0.8 × V
DDQ
0.6
1.0
1.15 R
ZQ
/TISF
PUPD
1, 2, 3, 4, 5
R
TT
30PU60
,
R
TT
20PU40
Notes:
1. TISF
PUPD
: Termination Impedance Scaling Factor for Pull-Up and Pull-Down path:
TISF
PUPD
= 1 for R
TT
120PU/PD240
TISF
PUPD
= 2 for R
TT
60PU/PD120
TISF
PUPD
= 3 for R
TT
40PU/PD80
TISF
PUPD
= 4 for R
TT
30PU/PD60
TISF
PUPD
= 6 for R
TT
20PU/PD40
2. The tolerance limits are specified after calibration with stable voltage and temperature. For the behavior of the tolerance
limits if temperature or voltage changes after calibration, see the above section ODT temperature and voltage sensitivity.
3. The tolerance limits are specified under the condition that V
DDQ
= V
DD
and that V
SSQ
= V
SS
.
4. Pull-down and pull-up ODT resistors are recommended to be calibrated at 0.5 × V
DDQ
. Other calibration schemes may be
used to achieve the linearity spec shown above, e.g. calibration at 0.2 × V
DDQ
and 0.8 × V
DDQ
.
5. Not a specification requirement, but a design guide line.