PCB Assembly Considerations
1. Surface mount the sensor and all other electrical com-
ponents into PCB.
2. Reflow the entire assembly in a no-wash solder
process.
3. Place the lens onto the base plate. Care must be taken
to avoid contaminating or staining the lens.
4. Remove the protective kapton tape from optical ap-
erture of the sensor and LED. Care must be taken to
keep contaminants from entering the aperture. Rec-
ommend not to place the PCB facing up during the en-
tire mouse assembly process. Recommend to hold the
PCB first vertically for the kapton removal process.
5. Insert PCB assembly over the lens onto the base plate
aligning post to retain PCB assembly. The lens piece
has alignment posts which will mate with the align-
ment holes on the sensor aperture.
6. The optical position reference for the PCB is set by the
base plate and lens. Note that the PCB motion due to
button presses must be minimized to maintain optical
alignment.
7. Install mouse top case. There MUST be a feature in the
top case to press down onto the sensor to ensure the
sensor and lens components are interlocked to the
correct vertical height.
Design Considerations for Improved ESD Performance
For improved electrostatic discharge performance, typi-
cal creepage and clearance distance are shown in the
table below. Assumption: base plate construction as per
the Avago Technologies supplied IGES file and ADNS-
3150-001 lens.
Typical Distance
Creepage
Clearance
Millimeters
0.6
2.76
Note that the lens material is polycarbonate and there-
fore, cyanoacrylate-based adhesives or other adhesives
that may damage the lens should NOT be used.
BOTTOM OF PCB TO
BOTTOM MATING
SURFACE OF LENS
2.28
(0.09)
SENSOR
CUSTOMER'S PCB
CUSTOMER'S
BASE PLATE
3.25
BOTTOM OF PCB TO
NAVIGATION SURFACE (0.13)
2.50 DIE TO NAVIGATION
(0.10) SURFACE
0.29
LENS
(0.01)
BOTTOM OF LENS
TO NAVIGATION SURFACE
NAVIGATION
SURFACE
0.97
(0.04)
BOTTOM MATING SURFACE
OF LENS TO NAVIGATION SURFACE
Figure 6a. Sectional view of PCB assembly
LED DIE
CUSTOMER'S PCB
SENSOR DIE
CUSTOMER'S BASE PLATE
LENS
SENSOR PCB
NAVIGATION
SURFACE
Figure 6b. Sectional view of PCB assembly highlighting optical mouse components
6
AVAGO [ AVAGO TECHNOLOGIES LIMITED ]
