2

Figure 1. Sectional view of PCB assembly highlighting all optical mouse components

(optical mouse sensor, clip, lens, LASER, PCB, and base plate).

SENSOR

VSCEL PCB

BASE PLATE

LENS

SURFACE

VSCEL

CLIP

PCB

The Texas Instruments MSP430F1222 is the

ultra low-power mixed signal microcontroller

with a built-in 16-bit timer, 10-bit A/D converter

with integrated reference and data transfer

controller (DTC) and twenty-two I/O pins. In

addition, the MSP430F1222 microcontroller has

built-in

communication

capability

using

asynchronous (UART) and synchronous (SPI)

protocols. The architecture, combined with five

low power modes is optimized to achieve

extended battery life on wireless application.

The Nordic nRF2402 and nRF2401A are the

low power single-chip radio transmitter and

transceiver for the world wide 2.4 - 2.5 GHz

ISM band. The entire transmitter and transceiver

including all inductors and filters are integrated

in each single chip respectively which gives the

lowest cost solution to the end user. All

configurations of the nRF2402 transmitter and

nRF2401A transceiver are done via a standard

serial interface. The nRF devices include the

ShockBurst engine which allow for high datarates

on

air

using

low

datarates

between

the

microcontroller and the nRF device, it will also

automatically validate the packets adress and

CRC, further reducing the microcontrollers

processing tasks.

The

Cypress

CY7C63231A

enCoRe

 is a

revolutionary chip that integrates numerous

common components, including breakthrough

crystal-less oscillator. The result is an overall

reduction in board components and reduced

system cost. The EPROM based microcontroller

allows easy firmware modification, as well as

storage of Vendor and Product ID

s without

an external EEPROM.

This kit is connectable to a PC via the USB

port. It is based on the 2.4GHz RF technology,

the data generated from displacement detection

/ button status in the laser mouse is encoded

with a pre-defined serial type protocol handled

by firmware in the MCU. In the RF stage, the

encoded data is used for GFSK modulation.

The captured data from the RF receiver stage

is decoded with a corresponding packet format

used for mouse applications. The final data is

sent to the host through the USB interface.