MIKROE Proximity 10 Click

Proximity 10 Click is a versatile proximity detection device on a Click board™. It can detect a foreign object distanced up to 200cm. The Click board™ features a detection sensor IC that can trigger a programmable-event interrupts, which makes this Click board™ capable of detecting even simple gesture movements. The advanced onboard IC sensor features LED driver section, a light sensor with the integrated analog front end (AFE), 16 bit analog to digital converter (ADC), and digital engine for processing and aggregation of the measurement result, which simplifies the firmware development. The ambient light cancellation includes both digital and optical filtering, resulting in increased detection reliability.

Proximity 10 Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.

With its high sensitivity and signal to noise ratio, this Click board™ is ideally suited for a range of applications that rely on accurate and reliable proximity detection. It can be used for proximity activated surveillance systems, equipment lid closing, object proximity detection, simple gesture activated HID interface, and other similar applications which rely on an accurate object proximity detection.

The main sensor IC on the Click board™ is the SI1143, a photometric sensor for the ambient light and proximity detection, from Silicon Labs. Among other sections, this IC contains a LED driver, used to drive an externally connected LED, which provides feedback for the SI1143 sensory sections. Therefore, the LED should be chosen so that its spectrum matches the spectral sensitivity of the on-chip light sensor. For this reason, the Click board™ is equipped with the narrow beam LED from Rohm Semiconductor with its spectral response characteristic peaking at 870nm, which is a perfect choice for this application.

The proximity detection consists of sending a pulse to the LED while measuring the response of the reflected light. Most of the parameters are user configurable, such as the sampling frequency, pulses duration, averaging parameters and more. More in-depth information about the registers can be found in the SI1143 datasheet. Aimed towards the low consumption market, the SI1143 uses a rather low voltage range, between 1.7V and 3.6V. Since the most of the MCUs use 3.3V, this Click board™ is designed so that the SI1143 IC is directly interfaced with the mikroBUS™.

Proximity 10 Click offers an interrupt output pin that can be used to trigger an interrupt on the host MCU. The SI1143 IC interrupt engine allows several interrupt sources, which can be used to trigger a state change on the INT pin. These sources include proximity detection interrupts (proximity OFF and proximity ON), sample interrupts, and more. The INT pin itself is highly configurable, and when asserted, this pin triggers an MCU interrupt, informing it that the configured interrupt event has occurred. The MCU can then read the desired register output, not having to poll it constantly, which saves both MCU cycles and power. The INT pin is routed via the level shifting IC to the mikroBUS™ INT pin.

As already mentioned, detailed information on the SI1143 IC registers can be found in the datasheet. However, MikroElektronika provides a library that contains functions compatible with the MikroElektronika compilers, which can be used for simplified programming of the Proximity 10 Click. The library also contains an example application, which demonstrates its use. This example application can be used as a reference for custom designs.

• Interface: GPIO, I²C
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 254mm
• Input Voltage: 3.3V