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PixArt Imaging Inc. http://www.pixart.com

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Version 1.0 | 05 Sep 2016 | 11010AEN

PixArt Imaging Inc.

ADBS-A350 General Datasheet

Optical Finger Navigation Chip

ADBS-A350 General Datasheet

Optical Finger Navigation Chip

Overview of Optical Chip Assembly

PixArt Imaging provides an IGES file drawing describing the cover plate molding features.

Chip Assembly

The components interlock as they are mounted onto defined features on the cover plate. The ADBS-A350 chip is

designed for surface mounting on a PCB, looking up. There is an aperture stop and features on the package that

align to the lens.

The lens provides optics for the imaging of the surface as well as illumination of the surface at the optimum angle.

Features on the lens align it to the chip and cover plate. Contamination must be kept away from the lens. During

assembly process, it is recommended to use a minimum of a 10K clean room environment or equivalent laminar

flow workbench.

PCB Assembly Considerations

1. Surface mount the chip and all other electrical components into PCB.

2. Reflow the entire assembly in a no-wash solder process.

3. Remove the protective kapton tape from optical aperture of the chip and LED. Care must be taken to keep

contaminants from entering the aperture. Recommend not to place the PCB facing up during the entire assembly

process. Recommend to hold the PCB first vertically for the kapton removal process.

4. Press fit the lens onto the chip until there is no gap between the lens and chip, with force up to maximum 2.2

kgf. Care must be taken to avoid contaminating or staining the lens. The lens piece has alignment posts which

will mate with the alignment holes on the chip package.

5. Place and secure the optical navigation cover onto the lens to ensure the chip and lens components are always

interlocked to the correct vertical height. The cover design has a foolproof feature to avoid wrong orientation of

the cover.

6. The optical position reference for the PCB is set by the navigation cover and lens.

7. Install device top casing. There MUST be a feature in either top casing or bottom casing to press onto the chip

to ensure the chip and lens components are always interlocked to the correct vertical height.

Figure 3. Recommended PCB PADOUT and spacing