AMBIENT 6 CLICK
PID: MIKROE-3444 Weight: 18 g
Ambient 6 click can sense the intensity of the ambient light, providing the
measurement data in digital format over the I2C interface. It utilizes the VEML7700, a
miniature ambient light sensor (ALS) with I2C interface. Packed in a small transparent
casing, this sensor can provide very accurate readings: thanks to a 16-bit dynamic
range, it can be used in very dim and very bright lighting conditions. A well-proven
Filtron™ technology allows response close to a real human eye, while the O-Trim™
technology allows for ALS tolerance less than 10%. The flicker noise rejection algorithm
further improves accuracy, while excellent thermal compensation ensures consistency
of the measurement results.
Ambient 6 click is supported by a mikroSDK compliant library, which includes functions
that simplify software development. This Click board™ comes as a fully tested product,
ready to be used on a system equipped with the mikroBUS™ socket.
Thanks to the used proprietary technologies that allow high precision, reliability, and low
power consumption, Ambient 6 click can be used for a rapid development of various
cost-effective applications that rely on light intensity sensing, including optical switches,
backlight dimming applications for mobile and handheld devices, light metering
applications (lux meters), and similar.
HOW DOES IT WORK?
The main component of the Ambient 6 click is the VEML7700, a high accuracy ambient
light sensor (ALS) with I2C interface, from Vishay Semiconductors. This sensor utilizes
several proprietary technologies to ensure accurate measurements of the light intensity,
with the spectral response very close to a human eye. By utilizing a sensitive photodiode, low noise amplifier, and a 16-bit A/D converter (ADC), this sensor can provide
the data directly, with no need for complex calculations. The dynamic range for the
ambient light sensor is very large, starting down from 0 lx up to about 167 klx, with the
maximum resolution of only 0.005 lx/count. A high dynamic range along with a linear
response to different light sources, allows this sensor to be placed behind a dark glass
or panels made of other semi-transparent materials.
The VEML7700 sensor uses only six 16-bit registers, which makes it very simple to
configure and use. Even though, it comes with the mikroSDK compatible library, which
simplifies the development even more. However, more detailed explanation of each
command can be found in the datasheet of the VEML7700, if required.
By using these six registers, the user can configure the Click board™ and the equipped
VEML7700 sensor, fine-tuning it according to the requirements of the application. All the
working parameters including the sensitivity, integration time, interrupt detection,
persistence protection for the interrupt triggering, low and high threshold window for the
interrupt, can all be set using these registers. Finally, the Ambient Light Sensing (ALS)
result can be found here in 16-bit register 0x04. The data can be read or written in
LSB/MSB format, using the 8-bit I2C interface.
A selectable sensitivity allows a very wide dynamic range for the ALS measurement.
There are two ALS_SM bits, allowing the sensitivity to be set to 1/4, 1/8, 2, and 1 x ALS
nominal sensitivity. This offers four different luminosity ranges to be covered for each
selected integration time (ALS_IT). For example: the fastest integration time (25ms)
results in the lowest resolution, and combined with the sensitivity of 1/8 x ALS, it allows
the highest luminosity value to be measured.
The event detection engine allows optimized firmware to be developed. Although there
is no dedicated interrupt pin on the VEML7700 IC, the software can still poll the status
by reading two event flag bits. When any of the programmed light thresholds is
exceeded for a programmed number of times (persistence protection), an interrupt
event will be generated, asserting this pin to a LOW logic level. The interrupt pin is
routed to the mikroBUS™ INT pin.
The Click board™ is supported by the mikroSDK library, which contains functions for
simplified development. The mikroSDK functions are well-documented, but there is still
a need, the datasheet of the VEML7700 offers listing of all the registers and their
specific functions.
The Click board™ is designed to work with 3.3V only. When using it with MCUs that use
5V levels for their communication, a proper level translation circuit should be used.
SPECIFICATIONS
Type
Optical
Applications
It can be used for a rapid development of various cost-effective
applications that rely on light intensity sensing, including optical
switches, screen dimming applications for mobile and handheld
devices, light metering applications (lux meters), and similar.
On-board
modules
VEML7700, a high accuracy ambient light sensor (ALS) with I2C
interface, from Vishay Semiconductors.
Key Features
High resolution and range of light intensity that can be measured,
spectral response similar to human eye, low power consumption,
compact design ideal for building IoT applications, immune to
flickering and fluorescent light sources, independent of the light
source type, and more.
Interface
I2C
Input Voltage
3.3V
Click board
size
M (42.9 x 25.4 mm)
PINOUT DIAGRAM
This table shows how the pinout on Ambient 6 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
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
Label
Name
Default
LD1
PWR
-
Description
Power LED indicator
SOFTWARE SUPPORT
We provide a library for the Ambient 6 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
Library initializes and defines I2C bus driver and driver functions which offer a choice to
write data in registers and to read data from registers. Library also offers a choice to
reads ambient data and ambient light in LUX. The user also has the function for
configuration chip.
Key functions:
uint16_t ambient6_getAmbientData() - Functions for read 16bit Ambient Data (ALS).
float ambient6_getAmbientLight() - Functions for get Ambient Light Data.
void ambient6_configuration(uint16_t configData) - Functions for configuration device for
measurement.
Examples description
The application is composed of the three sections :
System Initialization - Initializes I2C module.
Application Initialization - Initialization driver init and default configuration device for measurement.
Application Task - (code snippet) - Read Ambient Light in lux[lx] and this data logs to USBUART
every 1sec.
void applicationTask()
{
char demoText[ 50 ];
float AmbientLight;
AmbientLight = ambient6_getAmbientLight();
FloatToStr(AmbientLight,demoText);
demoText[ 7 ] = 0;
mikrobus_logWrite(" Ambient Light : ", _LOG_TEXT);
mikrobus_logWrite(demoText, _LOG_TEXT);
mikrobus_logWrite(" lx", _LOG_LINE);
Delay_1sec();
}
The full application code, and ready to use projects can be found on our LibStock page.
Other mikroE Libraries used in the example:
I2C
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.
https://www.mikroe.com/ambient‐6‐click/4‐23‐19