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196
Lucent Technologies Inc.
Preliminary Data Sheet, Rev. 1 , Rev. 1
September 1998
ORCA Series 3 FPGAs
Package Coplanarity
The coplanarity limits of the
ORCA Series 3 packages
are as follows.
Package Parasitics
The electrical performance of an IC package, such as
signal quality and noise sensitivity, is directly affected
by the package parasitics. Table 76 lists eight parasitics
associated with the
ORCA packages. These parasitics
represent the contributions of all components of a
package, which include the bond wires, all internal
package routing, and the external leads.
Four inductances in nH are listed: LSW and LSL, the
self-inductance of the lead; and LMW and LML, the
mutual inductance to the nearest neighbor lead. These
parameters are important in determining ground
bounce noise and inductive crosstalk noise. Three
capacitances in pF are listed: CM, the mutual capaci-
tance of the lead to the nearest neighbor lead; and C1
and C2, the total capacitance of the lead to all other
leads (all other leads are assumed to be grounded).
These parameters are important in determining capaci-
tive crosstalk and the capacitive loading effect of the
lead. The lead resistance value, RW, is in m
.
The parasitic values in Table 78 are for the circuit
model of bond wire and package lead parasitics. If the
mutual capacitance value is not used in the designer’s
model, then the value listed as mutual capacitance
should be added to each of the C1 and C2 capacitors.
Table 78. Package Coplanarity
Package Type
Coplanarity Limit
(mils)
EBGA
8.0
PBGA
8.0
SQFP/SQFP2
4.0 (240-Pin)
3.15 (208-Pin)
Figure 100. Package Parasitics
Table 79. Package Parasitics
Package Type
LSW
LMW
RW
C1
C2
CM
LSL
LML
208-Pin SQFP
4
2
200
1
7—10
4—6
208-Pin SQFP2
4
2
200
1
6—9
4—6
240-Pin SQFP
4
2
200
1
8—12
5—8
240-Pin SQFP2
4
2
200
1
7—11
4—7
256-Pin PBGA
5
2
220
1
5—8
2—4
352-Pin PBGA
5
2
220
1.5
7—12
3—6
432-Pin EBGA
4
1.5
500
1
0.3
3—5.5
0.5—1
600-Pin EBGA
4
1.5
500
1
0.4
3—6
0.5—1
5-3862(C)2
PAD N
LSW
RW
BOARD PAD
CM
C1
LSW
RW
LSL
LMW
C2
C1
LML
C2
LSL
PAD N + 1