AMBIENT 7 CLICK
PID: MIKROE-3601
Weight: 25 g
Ambient 7 Click is a light intensity-sensing and measuring Click board™, which
features an accurate light-intensity sensor labeled as SFH 5701 A01, made by Osram
Opto Semiconductors. It offers a high measurement accuracy in wide range of the
actual light intensity. The spectral response of the sensor is calibrated to closely match
the spectral response of the human eye. Thanks to its high level of integration, the
sensor requires a minimal number of external components.
Ambient 7 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.
The influence of the light source type on the measurement accuracy is quite reduced.
The sensor is capable of converting the light intensity from any type of light source,
including daylight, fluorescent light, LED light, incandescent light, and so on. It also
features Integrated dark current suppression and thermal compensation, which helps
eliminating enviromental effects to measurement results. Its low power consumption,
compact size, and high sensitivity, make this sensor an ideal solution for both the IoT
light-sensing applications, but also for portable or handheld devices which utilize an
accurate light intensity sensing, such as the TFT/LCD screens, keypad backlight, Smart
TVs, cell phones, digital cameras, and similar.
HOW DOES IT WORK?
As mentioned previously, Ambient 7 click uses the SFH 5701 A01, an accurate lightintensity sensor from Osram Opto Semiconductors. This sensor has many features that
make it a perfect solution for small designs such as the Ambient 7 Click board™. One of
these features is certainly its high level of integration, that allows a minimal number of
external components, leaving room for an additional operational amplifier, labeled as
OPA344, made by Texas Instruments, proven in many designs.
As the SFH 5701 A01 limits the output current proportionaly to ambient light intensity, it
creates an analog voltage on the R2 resistor (shunt). That voltage is directly
proportional to the flowing current and thus the ambient light intensity. The previously
mentioned operational amplifier serves as a unity gain amplifier (buffer), to ensure good
analog measurement signal integrity. The output of the unity gain amplifier is routed to
the mikroBUS™ AN pin. The voltage on the AN pin can be measured bz internal ADC
integrated in the main MCU on the development board.
The accuracy of SFH 5701 A01 sensor is not influenced by the light source type. It is
calibrated so its spectral response is closely matched to a spectral response of the
human eye. It is also worth to mention that the sensor qualification test plan is
referenced to the guidelines of AEC-Q102 – a failure mechanism based stress test
qualification for discrete optoelectronic semiconductors in automotive applications.
Built in thermal compensation ensures that the measurement results are valid in wide
temperature range and thanks to integrated dark current suppression, the output signal
while the sensor is exposed to dark environment is as minimal as possible. The sensor
is operational in very wide Illuminance range – from 0.01lx up to 10000lx. In other
words, it has linear response over 6 decades of illumination range.
This Click Board™ is designed to be operated only with 5V logic level. A proper logic
voltage level conversion should be performed before the Click board™ is used with
MCUs with logic levels of 3.3V.
SPECIFICATIONS
Type
Optical
Applications
This sensor is an ideal solution for both the IoT light-sensing
applications, but also for portable or handheld devices which utilize
an accurate light intensity sensing, such as the TFT/LCD screens,
keypad backlight, Smart TVs, cell phones, digital cameras, and
similar.
On-board
modules
SFH 5701 A01, an accurate light-intensity sensor from Osram Opto
Semiconductors.
Key Features
A spectral response similar to human eye, low power consumption,
Integrated dark current suppression, Built in thermal compensation,
Linear response over 6 decades of illumination range
Interface
Analog
Input Voltage
5V
Compatibility
mikroBUS
Click board
size
S (28.6 x 25.4 mm)
PINOUT DIAGRAM
This table shows how the pinout on Ambient 7 click corresponds to the pinout on the
mikroBUS™ socket (the latter shown in the two middle columns).
Notes
Analog Out
Ground
Pin
Pin
AN
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
NC
NC
6
MOSI
SDA
11
NC
NC
7
3.3V
5V
10
5V
GND
8
GND
GND
9
GND
Notes
Power supply
Ground
ONBOARD JUMPERS AND SETTINGS
Label
Name
Default
LD1
PWR
-
Description
Power LED Indicator
SOFTWARE SUPPORT
We provide a library for the Ambient 7 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
The library contains ADC functions to completely setting and reading the value from the
ADC channel that sends Ambient click. The ambient light measurement resolution
depends on the ADC resolution you use.
Key functions:
void ambient7_adcInit() - ADC init.
void ambient7_adcSetInputChannel() - ADC set input channel.
uint32_t ambient7_adcRead() - ADC read data.
Examples description
The application is composed of three sections :
System Initialization - Initializes UART for logging data.
Application Initialization - Initialization driver init and ADC init.
Application Task - Reads ADC value and this data logs to USBUART every 1 sec..
note - Illuminance range [EV] - from 0.01[lx] to 10k[lx] depending on the ADC you are using.
void applicationTask()
{
uint16_t ADC_value;
char demoText[ 50 ];
ADC_value = ambient7_adcRead();
WordToStr(ADC_value, demoText);
mikrobus_logWrite(" ADC value: ", _LOG_TEXT);
mikrobus_logWrite(demoText, _LOG_LINE);
Delay_ms( 500 );
}
The full application code, and ready to use projects can be found on our LibStock page.
Other mikroE Libraries used in the example:
ADC Library.
Conversions Library.
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‐7‐click/6‐28‐19
