Datasheet
DocID8349 Rev 7 153/170
ST7LITE20F2 ST7LITE25F2 ST7LITE29F2 Package characteristics
169
14.2 Soldering information
In accordance with the RoHS European directive, all STMicroelectronics packages have
been converted to lead-free technology, named ECOPACK
TM
.
• ECOPACK
TM
packages are qualified according to the JEDEC STD-020C compliant
soldering profile.
• Detailed information on the STMicroelectronics ECOPACK
TM
transition program is
available on www.st.com/stonline/leadfree/, with specific technical Application notes
covering the main technical aspects related to lead-free conversion (AN2033, AN2034,
AN2035, AN2036).
Backward and forward compatibility
The main difference between Pb and Pb-free soldering process is the temperature range.
• ECOPACK
TM
TQFP, SDIP and SO packages are fully compatible with Lead (Pb)
containing soldering process (see application note AN2034)
• TQFP, SDIP and SO Pb-packages are compatible with Lead-free soldering process,
nevertheless it's the customer's duty to verify that the Pb packages maximum
temperature (mentioned on the Inner box label) is compatible with their Leadfree
soldering temperature.
Table 90. Thermal characteristics
Symbol Ratings Value Unit
R
thJA
Package thermal resistance
(junction to ambient)
SO20
DIP20
125
63
°C/W
T
Jmax
Maximum junction temperature
(1)
1. The maximum chip-junction temperature is based on technology characteristics.
150 °C
P
Dmax
Power dissipation
(2)
2. The maximum power dissipation is obtained from the formula P
D
= (T
J
-T
A
) / R
thJA
.
The power dissipation of an application can be defined by the user with the formula: P
D
=P
INT
+P
PORT
where P
INT
is the chip internal power (I
DD
xV
DD
) and P
PORT
is the port power dissipation depending on the
ports used in the application.
500 mW
Table 91. Soldering compatibility (wave and reflow soldering process)
Package Plating material devices Pb solder paste Pb-free solder paste
SDIP & PDIP Sn (pure Tin) Yes Yes
(1)
1. Assemblers must verify that the Pb-package maximum temperature (mentioned on the Inner box label) is
compatible with their Lead-free soldering process.
TQFP and SO NiPdAu (Nickel-palladium-Gold) Yes Yes
(1)