Ambient 18 Click Board

How Does The Ambient 18 Click Board™ Work?

The Ambient 18 Click Board™ uses the BH1680FVC, an analogue current-output ambient light sensor from Rohm Semiconductor. It is composed of photodiodes, amplifiers, and current mirror circuits and can detect a wide range of illuminance up to 10Klux, providing excellent responsivity close to the human eyes' response. It has stable performance over a wide temperature, voltage range, and a built-in shutdown function. It is characterized by good output linearity across a wide illumination range and low sensitivity variation across various light sources suitable to sense the amount of the present ambient light.

It also has four configurable modes of operation, shutdown mode associated with three gain modes: high-gain mode, medium-gain mode, and low-gain mode. The desired gain mode is selected through CS and PWM pins of the mikroBUS™ socket labelled as GC1 and GC2.

The output of the BH1680FVC can be converted to a digital value using MCP3221, a successive approximation A/D converter with a 12-bit resolution from Microchip, using a 2-wire I2C compatible interface, or can be sent directly to an analog pin of the mikroBUS™ socket labelled as AN. Selection can be performed by onboard SMD jumper labelled as ADC SEL to an appropriate position marked as AN and I2C.

The MCP3221 provides one single-ended input with low power consumption, a low maximum conversion current, and a Standby current of 250μA and 1μA, respectively. Data can be transferred at rates of up to 100kbit/s in the Standard and 400kbit/s in the Fast Mode. Also, maximum sample rates of 22.3kSPS with the MCP3221 are possible in a Continuous-Conversion Mode with a clock rate of 400kHz.

The Ambient 18 Click Board™ can operate with both 3.3V and 5V logic voltage levels selected via the VIO 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.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout on Ambient 18 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin		Pin	Notes
Analog Signal	AN	1	AN	PWM	16	GC1	Gain Mode Control Signal 2
NC	2	RST	INT	15	NC
Gain Mode Control Signal 1	GC1	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

AMBIENT 18 CLICK ELECTRICAL SPECIFICATIONS