256Mb: x4, x8, x16 SDRAM
Package Dimensions
Figure 10: 54-Ball VFBGA "B4/F4" (8mm x 8mm) (x16)
Seating plane
A
0.12
A
54X Ø0.45
Dimensions apply
to solder balls post-
Ball A1 ID
(covered by SR)
Ball A1 ID
reflow on∅Ø0.40 SMD
ball pads.
9
8
7
3
2
1
A
B
C
D
E
6.4 CTR
8 ±0.1
F
G
H
J
0.8 TYP
0.8 TYP
6.4 CTR
8 ±0.1
0.9 ±0.1
0.25 MIN
1. All dimensions are in millimeters.
2. Recommended pad size for PCB is 0.4mm ±0.065mm.
Notes:
3. Solder ball material: SAC305 (96.5% Sn, 3% Ag, 0.5% Cu) or SAC105 (98.5% Sn, 1% Ag,
0.5% Cu).
4. Topside part-marking decoder is available at www.micron.com/decoder.
PDF: 09005aef8091e6d1
256Mb_sdr.pdf - Rev. R 10/12 EN
Micron Technology, Inc. reserves the right to change products or specifications without notice.
18
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MICRON [ MICRON TECHNOLOGY ]
