15
Section 3 Installing the MCU to the User System
CAUTION
1. Check the location of pin 1 before inserting.
2. Use a provided screwdriver.
3. The tightening torque must be 0.054 N•m or less.
If the applied torque cannot be accurately measured,
stop tightening when the force required to turn the screw
becomes significantly greater than that needed when first
tightening. If a screw is tightened too much, the screw
head may break or an IC socket contact error may be
caused by a crack in the IC socket solder.
4. If the MCU does not operate correctly, cracks might have
occurred in the solder.
1. Attach the spacer and cover to the IC socket.
2. Place the spacer on the IC socket. Place the two guide pins of the spacer in the corresponding
holes on the IC socket.
3. Place the MCU gently in the opening of the spacer. Be sure to correctly align pin 1 of the
MCU with the IC socket. The solder balls of the MCU will then be in the correct locations
relative to the connection pins of the IC socket.
4. Put the cover on the spacer. The four holes at the four corners of the spacer and of the cover
must be aligned. Use the four screws to fasten the cover to the IC socket. Each screw in turn
should be made a little tighter, alternating between screws on opposing corners. Use the
screwdriver provided with the package. The torque in tightening must be 0.054 N
•
m or less.
5. When removing the cover from the IC socket, hold the side of the cover so that no stress is
applied to the soldered connections between the IC socket and user system while the screws
on the cover are being unscrewed. Use tweezers to remove the MCU from the opening in the
spacer,
