6

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

entire 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.

Typical Distance

Millimeters

Creepage

0.6

Clearance

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.

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

PixArt Imaging supplied IGES file and ADNS-

3150-001 lens.

Figure 6a. Sectional view of PCB assembly

Figure 6b. Sectional view of PCB assembly highlighting optical mouse components

LENS

DIE TO NAVIGATION

SURFACE

NAVIGATION

SURFACE

BOTTOM MATING SURFACE

OF LENS TO NAVIGATION SURFACE

BOTTOM OF LENS

TO NAVIGATION SURFACE

BOTTOM OF PCB TO

NAVIGATION SURFACE

BOTTOM OF PCB TO

BOTTOM MATING

SURFACE OF LENS

CUSTOMER'S PCB

3.25

(0.13)

2.28

(0.09)

0.29

(0.01)

0.97

(0.04)

2.50

(0.10)

SENSOR

CUSTOMER'S

BASE PLATE

NAVIGATION

SURFACE

CUSTOMER'S PCB

CUSTOMER'S BASE PLATE

SENSOR DIE

SENSOR PCB

LENS

LED DIE

PixArt Imaging Inc.

Low Power LED Integrated Slim Mouse Sensor

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PixArt Imaging Inc.