11. Input devices

Group assignment requirements

The group assignment for this week is the following: - Probe an input device(s)’s analog levels and digital signals - Document your work on the group work page and reflect on your individual page what you learned

Analog Signals

Sensor

The selected sensor is an LDR sensor. Find the datasheet here. An LDR (Light Dependent Resistor) sensor is an electronic component whose resistance changes based on the amount of light it receives. Widely used in applications like streetlights and camera exposure control, LDR sensors are cost-effective solutions for light detection in various electronic projects.

This sensor measures the ambient light level by detecting variations in resistance. When exposed to high light levels, the resistance decreases, and conversely, when exposed to low light levels, the resistance increases. This change in resistance is utilized to provide an electrical output that correlates with the amount of light falling on the sensor.

Observed signals

To observe the operation of this sensor, we probed it with an oscilliscope to showcase the change of output voltage depending on ambient light

Digital Signals

Sensor

For the digital sensor measurement, we used the ultrasonic sensor. Ultrasonic distance sensors are electronic devices that utilize ultrasonic waves to measure the distance between the sensor and an object, commonly employed in applications such as obstacle detection, level sensing, and proximity sensing in robotics and automation.

We utilized the oscilloscope to measure the voltage output of the ultrasonic analog sensor.

Using the oscilloscope, we observed how the voltage value changed with variations in measured distance.