September 18, 2006 Document No. 001-05356 Rev. *B 27
CY8C20234, CY8C20334, CY8C20434 Final Data Sheet 3. Packaging Information
3.2 Thermal Impedances
3.3 Solder Reflow Peak Temperature
Following is the minimum solder reflow peak temperature to achieve good solderability.
Table 3-1. Thermal Impedances per Package
Package Typical θ
JA
*
16 QFN**
46
o
C/W
24 QFN**
40
o
C/W
32 QFN**
27
o
C/W
48 QFN**
28
o
C/W
* T
J
= T
A
+ Power x θ
JA
** To achieve the thermal impedance specified for the ** package, the center
thermal pad should be soldered to the PCB ground plane.
Table 3-2. Solder Reflow Peak Temperature
Package Minimum Peak Temperature* Maximum Peak Temperature
16 QFN
240
o
C 260
o
C
24 QFN
240
o
C 260
o
C
32 QFN
240
o
C 260
o
C
48 QFN
240
o
C 260
o
C
*Higher temperatures may be required based on the solder melting point. Typical temperatures for solder are 220 ± 5
o
C
with Sn-Pb or 245 ± 5
o
C with Sn-Ag-Cu paste. Refer to the solder manufacturer specifications.
