W255
Layout Example for DDR 2.5V Only
+2.5V Supply
FB
VDDQ2
0.005 mF 10 mF
C3
C4
G
G
1
G
V
48
47
46
45
V
G
G
2
3
4
G
G
5
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
6
7
8
9
G
G
G
V
V
G
G
G
10
11
12
G
V
G
V
G
G
G
13 G
14
G
15
16
17
18
19
20
21
22
23
G
G
V
G
V
G
G
G
G
28
27
26
25
G
G
G
V
G
24
FB = Dale ILB1206 - 300 (300:ꢀ@ 100 MHz) or TDK ACB 2012L-120
PF
PF
C4 = 0.005
V = VIA to respective supply plane layer
Ceramic Caps C3 = 10–22
= VIA to GND plane layer
G
Note: Each supply plane or strip should have a ferrite bead and capacitors
All bypass caps = 0.1ꢀPF ceramic
Rev 1.0,November 25, 2006
Page 7 of 9