Illuminance Click

How does it work?

Illuminance Click is based on the TSL2583, a high-sensitivity light-to-digital converter from ams AG. The TSL2583 combines one broadband photodiode (visible plus infrared) and one infrared-responding photodiode on a single CMOS integrated circuit capable of providing a near-photopic response over an effective 16-bit dynamic range (16-bit resolution). Two integrating analog-to-digital converters (ADC) convert the photodiode currents to a digital output representing the irradiance measured on each channel. Besides general-purpose light sensing applications, the TSL2583 is explicitly designed for displays (LCD, OLED) to extend battery life and provide optimum viewing in diverse lighting conditions.

The TSL2583 communicates with the MCU using the standard I2C 2-Wire interface with a maximum frequency of 400kHz. Besides, it allows choosing the least significant bit (LSB) of its I2C slave address using the SMD jumper labeled I2C ADD. An integration of both ADC channels co-occurs. Upon completion of the conversion cycle, the conversion result is transferred to the Channel 0 and Channel 1 data registers, respectively. The transfers are double-buffered to ensure that the integrity of the data is maintained. After the transfer, the device automatically begins the next integration cycle.

This sensor also supports an interrupt feature, routed to the INT pin on the mikroBUS™ socket, that simplifies and improves system efficiency by eliminating the need to poll a sensor for a light intensity value. The purpose of the interrupt function is to detect a meaningful change in light intensity, where the user can define the concept of a significant change in light intensity and time or persistence. Users can define a threshold above and below the current light level, where an interrupt generates when the conversion value exceeds either of these limits.

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. However, the Click board™ 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 Illuminance 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	INT	Interrupt
	NC	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

Illuminance Click electrical specifications

Software Support

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

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

Library Description

This library contains API for Illuminance Click driver.

Key functions

• This function gets Visible & Infrared value.

• This function calculates lux value from the TSL2561 sensor.

Example Description

This example demonstrates basic Illuminance Click functionality – calculates illuminance measured by sensor and logs results to UART Terminal.

 void application_task ( void ) 
 { 
     illuminance_get_result( &illuminance, &value_ch0, &value_ch1 ); 

     lux_value = illuminance_calculate_lux( ILLUMINANCE_TSL2561_GAIN_0X, ILLUMINANCE_TSL2561_INTEGRATIONTIME_402MS , value_ch0, value_ch1 ); 
     Delay_ms( 1000 ); 

     if ( ( ( lux_value - lux_value_old ) > sensitivity ) && ( ( lux_value_old - lux_value ) > sensitivity ) ) 
     { 
         log_printf( &logger, "rn--------------------------------" ); 
         log_printf( &logger, "rnFull  Spectrum: %u [ lux ]", lux_value ); 
         log_printf( &logger, "rnVisible  Value: %u [ lux ]", value_ch0 - value_ch1 ); 
         log_printf( &logger, "rnInfrared Value: %u [ lux ]", value_ch1 );     
         log_printf( &logger, "rn--------------------------------rn" ); 

         lux_value_old = lux_value; 
     } 
 }

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

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Illuminance

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 MikroElektronika compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MikroElektronika 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.