Input Sensors in Digital Systems
Note
- Digital systems often follow an input–process–output model.
- At the input stage, sensors are used to detect changes in the environment and feed this data into the system for further processing.
Common Sensors and Their Uses:
| Sensor Type | What It Detects | Example Use Case |
|---|---|---|
| Accelerometer | Motion / tilt / vibration | Step counter in smartwatches |
| Ultrasonic | Distance / proximity | Parking sensors in cars |
| Photoresistor | Light levels | Auto-brightness in phone screens |
| Voltage sensor | Voltage / electrical levels | Soil moisture monitoring (moisture = voltage) |
| Hygrometer | Humidity & air temperature | Smart thermostats, weather stations |
| Pressure sensor | Atmospheric / barometric pressure | Altimeters in drones or aircraft |
| Microphone | Sound / audio waves | Voice commands in smart speakers |
| Infrared sensor | Heat / radiation | Motion detection in security systems |
Tip
When selecting a sensor, consider the specific requirements of the application, such as accuracy, range, and environmental conditions.
Example
- In a smart irrigation system, moisture sensors measure soil humidity.
- If the soil is too dry, the system activates a pump to water the plants, optimizing water usage and ensuring plant health.
Example
Smartphones
- Accelerometers detect screen orientation and enable features like shake-to-wake.
- Microphones enable voice commands and noise cancellation.
