Datasheet

DDR3
DIMM1
1.5 V
VREF1
_
+
1 kW
DPOT
TPL0401A/B
OP-AMP
LMV321
1 kW
TPL0401A
TPL0401B
TPL0401C
www.ti.com SLIS144A –SEPTEMBER 2011–REVISED MARCH 2012
TYPICAL APPLICATION
Figure 15. DDR3 Voltage Reference Adjustment
Below table shows Ideal values of resistance for a 10kΩ DPOT. The absolute values can vary significantly, but
the ratio (Rhw/Rwl) is extremely accurate.
Table 1. Resistance Values Table
Step Binary Rwl (kΩ) Rhw (kΩ) Rhw/Rwl
0 0 0.00 10.00 0.00
1 1 0.08 9.92 0.01
2 10 0.16 9.84 0.02
3 11 0.23 9.77 0.02
4 100 0.31 9.69 0.03
5 101 0.39 9.61 0.04
6 110 0.47 9.53 0.05
7 111 0.55 9.45 0.06
8 1000 0.63 9.38 0.07
9 1001 0.70 9.30 0.08
10 1010 0.78 9.22 0.08
11 1011 0.86 9.14 0.09
12 1100 0.94 9.06 0.10
13 1101 1.02 8.98 0.11
14 1110 1.09 8.91 0.12
15 1111 1.17 8.83 0.13
16 10000 1.25 8.75 0.14
17 10001 1.33 8.67 0.15
18 10010 1.41 8.59 0.16
19 10011 1.48 8.52 0.17
20 10100 1.56 8.44 0.19
21 10101 1.64 8.36 0.20
22 10110 1.72 8.28 0.21
23 10111 1.80 8.20 0.22
24 11000 1.88 8.13 0.23
25 11001 1.95 8.05 0.24
26 11010 2.03 7.97 0.25
27 11011 2.11 7.89 0.27
28 11100 2.19 7.81 0.28
29 11101 2.27 7.73 0.29
30 11110 2.34 7.66 0.31
31 11111 2.42 7.58 0.32
Copyright © 2011–2012, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Link(s): TPL0401A TPL0401B TPL0401C