Light 2 Click

How does it work?

Light 2 Click is based on the ISL76682, an automotive low-power, high-sensitivity, light-to-digital sensor with an I2C interface from Renesas. Designed for precise light measurement, the ISL76682 features a state-of-the-art photodiode array that closely mimics the human eye’s response while effectively rejecting UV and infrared light. It includes an ADC that eliminates flickers at 50Hz and 60Hz from artificial lighting. Users can adjust the light measurement range through the I2C interface, with four selectable ranges from as low as 0.015lux up to 64.000lux, enhancing the flexibility and accuracy of light intensity readings. It’s ideally suited for automotive interior lighting adjustment, display backlighting control, and light measurement in industrial and medical environments.

The ISL76682 operates with low energy consumption, typically around 55µA in its Standard mode. It includes options for further reducing power usage through two power-down modes. The automatic power-down function turns off the sensor after each light measurement cycle when set to polling mode, while a software-controlled mode via the I2C interface can lower the power draw to less than 1µA. The ISL76682 outputs a simple code corresponding to the lux level, offers up to 16-bit resolution, and adapts to various lighting conditions, including direct sunlight.

Light 2 Click uses a standard 2-wire I2C interface to communicate with the host MCU, supporting Standard mode with up to 400kHz of frequency clock. In addition to I2C pins, the device allows the selection of I2C slave address between 0x44 and 0x45 via an SMD jumper marked as ADDR SEL.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used as a reference for further development.

Specifications

Pinout diagram

This table shows how the pinout on Light 2 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
	NC	2	RST	INT	15	NC
ID COMM	CS	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	NC	5	MISO	SCL	12	SCL	I2C Clock
	NC	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Light 2 Click electrical specifications

Software Support

We provide a library for the Light 2 Click as well as a demo application (example), developed using MIKROE compilers. The demo can run on all the main MIKROE development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Light 2 Click driver.

Key functions

• light2_read_raw_data This function reads raw data from the ADC of Light 2 click board.

• light2_get_cal_const This function is used to get a calculation constant depending on Light 2 click board configuration.

• light2_get_light_data This function is used to read light data of Light 2 click board configuration.

Example Description

This example demonstrates the use of Light 2 click board by measuring the ambient light level in Lux.

void application_task ( void )  
 { 
     float lux_data = 0; 

     light2_get_light_data( &light2, &lux_data ); 
     log_printf( &logger, " LUX data: %.2f LUX rn", lux_data ); 

     Delay_ms( 1000 ); 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Light2

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MIKROE compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MIKROE Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.