Proximity 13 Click

How does it work?

Proximity 13 click features touchless sensor IC that includes dual 23-bit analog-to-digital converters, an integrated high-sensitivity array of visible and infrared photodiodes, a digital signal processor, and three integrated LED drivers with programmable drive levels. The photodiode response and associated digital conversion circuitry provide excellent immunity to artificial light flicker noise and natural light flutter noise.

By default, the measurement parameters are optimized for indoor ambient light levels, where it is possible to detect low light levels. For operation under direct sunlight, the ADC can be programmed to operate in a high signal operation so that it is possible to measure direct sunlight without overflowing.

The Proximity 13 click is capable of measuring visible and infrared light. However, the visible photodiode is also influenced by infrared light. The measurement of illuminance requires the same spectral response as the human eye. If an accurate lux measurement is desired, the extra IR response of the visible-light photodiode must be compensated. Therefore, to allow the host to make corrections to the infrared light’s influence, SI1153-AB09-GMR reports the infrared light measurement on a separate channel. The separate visible and IR photodiodes lend themselves to a variety of algorithmic solutions. The host can then take these two measurements and run an algorithm to derive an equivalent lux level as perceived by a human eye. Having the IR correction algorithm running in the host allows for the most flexibility in adjusting for system-dependent variables. For example, if the glass used in the system blocks visible light more than infrared light, the IR correction needs to be adjusted.

Over distances of less than 50 cm, the dual-port active reflection proximity detector has significant advantages over single-port, motion-based infrared systems, which are only good for triggered events. Motion-based infrared detectors identify objects within proximity, but only if they are moving. Single-port motion-based infrared systems are ambiguous about stationary objects even if they are within the proximity field. The Proximity 13 click can reliably detect an object entering or exiting a specified proximity field, even if the object is not moving or is moving very slowly. However, beyond about 30–50 cm, even with good optical isolation, single-port signal processing may be required due to static reflections from nearby objects, such as tables, walls, etc. If motion detection is acceptable, the SI1153-AB09-GMR can achieve ranges of up to 50 cm, through a single product window.

Since the three infrared LEDs are placed in an L-shaped configuration, it is possible to triangulate an object within the three-dimensional proximity field. Thus, a touchless user interface can be implemented with the aid of host software.

Specifications

Pinout diagram

This table shows how the pinout on Proximity 13 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	+5V	Power supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Software Support

We provide a library for the Proximity 13 Click on our LibStock page, as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Library Description

Librari provides functions for reading and writing to registers. You have functions for setting parameters, sending commands and configurating device channels. There is function for reading all channels if they are enabled.

Key functions:

• uint8_t proximity13_generic_read ( uint8_t reg_adr ) – Generic read function from registers
• void proximity13_generic_write ( uint8_t reg_adr, uint8_t write_data ) – Generic write function to registers
• uint8_t proximity13_get_int_pin_status ( void ) – Function for reading status of int pin
• uint8_t proximity13_send_command ( uint8_t cmd_val ) – Function for sending commands
• uint8_t proximity13_set_parameter ( uint8_t param, uint8_t cmd_val ) – Function for setting parameters
• uint8_t porximity13_config_channel ( uint8_t chn_num, proximity13_cfg_t cfg_val ) – Function for configurating specific channel
• void proximity13_read_channels ( proximity13_chn_val_t *chn_val ) – Fucnction for reading from all enabled channels

Examples description

The application is composed of three sections :

• System Initialization – Initialization of I2C module and setting int pin to output
• Application Initialization – Check id status, configures device and sends command for measurement
• Application Task – Appliction measures values very 100ms and converts it to 24bit

void application_task ( )
{
    proximity13_chn_val_t chn_val;
    char txt[ 30 ];

    proximity13_read_channels( &chn_val );

    WordToStr( chn_val.channel_1, txt );
    mikrobus_logWrite( "Data :", _LOG_TEXT );
    mikrobus_logWrite( txt, _LOG_LINE );

    Delay_ms ( 100 );
}

The full application code, and ready to use projects can be found on our LibStock page.

Other mikroE Libraries used in the example:

• I2C
• UART
• Conversions

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. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.

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.