Ambient 19 Click is a compact add-on board used to measure the amount of the present ambient light. This board features the APM-16D24-310-DF8/TR8, a digital output ambient light and proximity sensor with an I2C interface and interrupt from Everlight Electronics. It has a flexible and wide operating range for the ambient light sensor with a maximum resolution of 0.0023Lux/count and full detectable illumination of 57880Lux. The proximity function has an adjustable number of IR pulses from 1 to 256, and a flexible IR LED driving current to meet different application requirements. It is also equipped with an integrated filter to reduce unwanted IR signals and noise from the environment. This Click board™ is the most suitable for obtaining ambient light data in applications such as automatic residential and commercial lighting management.

Ambient 19 Click as its foundation uses the APM-16D24-310-DF8/TR8, a digital I2C interface sensor that integrates Ambient Light Sensor (ALS), Proximity Sensor (PS), and Infrared LED (IR LED) from Everlight Electronics. The ALS can sense ambient light intensity that matches the human eye's response and enable the device to implement display dimming or lighting brightness control functions, helping to reduce power consumption. On the other side, the proximity sensor use IR LED reflection function to detect "away or close" to the object triggering the device to turn ON/OFF or some other specific function.

Three photodiodes are built in the APM-16D24-310-DF8/TR8, where each photodiode responds to different light spectra. This feature can distinguish different light sources and derive different illuminance conversion formulas according to various light sources. Also, it has a flexible and wide operating range for the ambient light sensor with a maximum resolution of 0.0023lux/count and full detectable illumination of 57880Lux. An integrated proximity function has an adjustable number of IR pulses from 1 to 256 alongside a flexible IR LED driving current to meet different application requirements. There is also an integrated filter to reduce unwanted IR signals and environmental noise.

The APM-16D24-310-DF8/TR8 does not require a specific Power-Up sequence but requires a voltage of 1.8V for its interface and logic part to work correctly. Therefore, a small regulating LDO, the MAX8511, is used, providing a 1.8V out of both 5V and 3.3V mikroBUS™ power rails.

Ambient 19 Click communicates with MCU using the standard I2C 2-Wire interface with a maximum clock frequency of 400kHz, fully adjustable through software registers. Since the sensor for operation requires a power supply of 3.3V, this Click board™ also features the PCA9306 and SN74LVC1T45 voltage-level translators. The I2C interface bus lines are routed to the voltage-level translators allowing this Click board™ to work with both 3.3V and 5V MCUs properly. It also possesses an additional interrupt signal, routed on the INT pin of the mikroBUS™ socket, indicating when a specific interrupt event occurs, such as detecting a meaningful change in light intensity.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

• Interface: I²C
• Compatibility: mikroBUS™
• Dimensions: 3.3V or 5V
• Supply Voltage: Min. 3.3V, Max. 5V
• ALS Detection Resolution: 0.0023 lx/count
• ALS Maximum Detection: 57880 lux
• ALS ADC Resolution: Min. 10 bit, Max. 16 bit
• PS ADC Resolution: Min. 8 bit, Max. 12 bit
• Operating Temperature Range: Min. -40°C, Typ. +25°C, Max. +85°C

• Schematic
• APM-16D24-310-DF8_TR8 Datasheet
• MAX8511 Datasheet
• PCA9306 Datasheet
• SN74LVC1T45 Datasheet
• mikroSDK
• LibStock