Texas Instruments Electronics Online Challenge
Entry ID #: 3606
Created: Wed, Jan 11, 2017 9:08 AM
Texas Instruments Electronics Online Challenge Introduction: The electronic device that was selected was a HP usb wired optical mouse. This computer mouse was selected for this challenge because it contained multiple components and was easy to disassemble. Components: Upon disassembly, many components were revealed. The first set of components were SW1 and SW2. These components were left click and right click buttons, respectively. The function of the left click and right click buttons is to send a signal when the user presses down on the left of right side of the mouse. The next set of components were SW3, LD1, and LQ1. SW3 is the middle click button and it sends a signal when the user presses down on the scroll wheel of the mouse. LD1 and LQ1 are sensors that sense how quickly the scroll wheel is being turned by the user. On the inner part of the scroll wheel are slits through which light can pass through. When the scroll wheel is not in use, the light passes through the slits. As the user rotates the scroll wheel with his or her finger, the slits block the light that is transmitted from LD1 to LQ1. The faster the light is being blocked and unblocked, the faster the mouse will tell the computer to scroll down a webpage. The next set of components were R1, R2, R3, R4, R5, and R6. These components are resistors which protect the mouse from too much current by reducing the current. Each resistor has a different combination of colored lines on it to show the resistance of that resistor. The next set of components were C1, C2, C3, C4, C5, and C6. These components are capacitors whose function is to store electrical energy when the mouse is connected by usb to the computer. It also is used to maintain a power supply when the mouse loses power. This is why the mouse will continue to have its LED on seconds after it has been unplugged from the computer. The next component found was XT1, but its function is unknown. The next set of components is U1 and LD2 which detect the motion of the mouse. Similar to LD1, LD2 is a LED light emitter, which shines a bright light onto a desk or other surface. The light is reflected from the surface back up to U1, a photocell light detector. As the mouse is moved across the surface, the pattern of light reflection changes, and the U1 component analyzes these changes to determine how the mouse is being moved. The last component is the J1 and it connects the mouse to the usb port of the computer and carries information. Conclusion: Although the mouse appears to be a simple piece of technology, it contains many components which transmit information from the mouse to the computer. It appeared that there were no Texas Instruments components inside the mouse but the capacitors were made by Jamicon. Overall, the computer mouse is an intricate technological device.