What is it?

This Si1141 breakout board is a lower-power I2C proximity and ambient light sensor. It can be used to detect objects that are 1cm to 200cm away. This is similar to sensors used in smartphones to detect if user has face touching phone or not.

Example use cases for Touch Proximity Sensors include:

Mobile devices: Touch Proximity Sensors are commonly used in smartphones and tablets to turn off the screen when the device is held close to the face during a call. They can also be used to detect when the user is reaching for the device, triggering an automatic wake-up function.

Home automation: Touch Proximity Sensors can be used to control lighting, heating, and cooling systems in homes and offices. For example, a sensor placed near the front door can detect when someone enters the room and automatically turn on the lights.

Robotics: Touch Proximity Sensors can be used in robotics to detect the presence of objects and prevent collisions. They can be used to provide object detection for mobile robots or as a safety feature in manufacturing processes.

Automotive: Touch Proximity Sensors can be used in cars to detect the presence of a driver or passenger and adjust settings such as seat position and climate control. They can also be used to detect when a person is approaching the car and unlock the doors automatically.

Medical devices: Touch Proximity Sensors can be used in medical devices to detect the presence of a person and provide touch-free control. For example, a sensor can be used in a wheelchair to detect when the user is approaching and activate the brakes to prevent accidental movement.

The Si1141 is an active optical reflectance proximity detector and ambient light sensor whose operational state is controlled through registers accessible through the I2C interface. The host can command the Si1141 to initiate on-demand proximity detection or ambient light sensing. The host can also place the Si114 in an autonomous operational state where it performs measurements at set intervals and interrupts the host either after each measurement is completed or whenever a set threshold has been crossed. This results in an overall system power saving allowing the host controller to operate longer in its sleep state instead of polling the Si1141.

This touchless proximity sensor boasts the industry's lowest power consumption of 9 μA average current (LED pulsed 25.6 μs every 800 ms at 180 mA plus 3 μA Si1141 supply.

Note: This board runs on 3.3V logic.