Temp&Hum 9 Click
PID: MIKROE‐3331
Weight: 23 g
Temp-Hum 9 click is a smart temperature and humidity sensing click
board™, packed with features that allow simple integration into any design.
It can measure a wide range of temperature and relative humidity values
with high accuracy. The SHTC3 sensors used on this Click board™ offers the
complete measurement system: capacitive RH sensor, bandgap thermal
sensor, analog and digital data processing, and the I2C communication
interface. Featuring a good reliability over time, high accuracy, and low
hysteresis, it is an ideal solution to be used in various temperature and
humidity related applications.
Temp-Hum 9 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.
Temp-Hum 9 click can measure the humidity in the range from 0 to 100
%RH and temperature in the range from -40
to +125
with a typical
accuracy of ±2 %RH and ±0.2 . It consumes very low amount of power
while operated, and it can output the conversion values directly in physical
units, thanks to the CMOSens® manufacturing technology. Featuring high
reliability and long-term stability, high Signal-to-Noise (SNR) ratio, good
accuracy, and low power consumption, Temp-Hum 9 click is an ideal solution
for development of a range of different applications, including battery
operated weather stations, thermostats and humidistats, microenvironment
centers, respiratory therapy applications, air conditioners, and other similar
applications.
How does it work?
The main component of Temp-Hum 9 click is the SHTC3, a relative humidity
and temperature sensor with I²C Interface, by Sensirion. This sensor IC
integrates two very accurate sensing components: temperature sensor, and
relative humidity sensor. By utilizing the proprietary CMOSens®
manufacturing technology, this sensor integrates the complete temperature
and humidity measurement system on chip. The output data is processed
and compensated by the SHTC3 IC itself, requiring only basic conversion
formulas to be applied within the firmware of the host microcontroller
(MCU). These conversion formulas are given in the SHTC3 datasheet, and
provide readings in °C and %RH, directly.
The SHTC3 incorporates an accurate bandgap temperature sensor, which
can measure the temperature in the range between -40°C and 125°C while
retaining accuracy of ±0.8°C, typically. The accuracy is even greater if the
range is narrowed down: when used over the range between 0°C and 60°C,
the typical accuracy is ±0.2°C. Also, the repeatability of the temperature
measurement is very good, in the range of 0.1°C. The SHTC3 sensor IC can
be reliably used for prolonged periods of time, as it has a very low thermal
drift of less than 0.02°C per year.
After the measurement has been converted by high-precision ADC, it is fed
to a logic back-end which applies factory-calibrated correction and converts
the raw data into a compensated value. By applying a simple conversion
formula, the temperature measurement can be read directly in . Note
however, that the sensor will take some time to accommodate to the
ambient temperature, especially if the temperature changes quickly,
considering the thermal conductivity of the PCB itself. However, the Click
board™ surface is not very large, resulting in lower thermal inertia.
The humidity sensor is a capacitor-based sensor which changes the
capacitance proportionally to the relative humidity. However, the
capacitance of this sensor is affected by changes of the ambient
temperature, as well. The datasheet of the SHTC3 offers a map of the RH
accuracy at different temperatures, covering a range of different values. The
RH sensor accuracy varies in the range between ±2% and ±4%, depending
on the measurement conditions. This table can be used to check the exact
accuracy for some specific
and %RH conditions.
After the measurement has been converted by high-precision ADC, it is fed
to a logic back-end which applies factory-calibrated correction and converts
the raw data into a compensated value. By applying a simple conversion
formula, the temperature measurement can be read directly in %RH. Note
that capacitor-based humidity sensors commonly suffer from a small
hysteresis, which may occur if the sensor is used in very humid conditions
for prolonged periods of time. However, this hysteresis is not irreversible.
The SHTC3 datasheet specifies that its hysteresis should stay within the
range of ±1 %RH.
Temp-Hum 9 click uses the I2C communication interface. It has pull-up
resistors connected to the mikroBUS™ 3.3V rail. A proper conversion of logic
voltage levels should be applied before the Click board™ is used with MCUs
operated with 5V.
Specifications
Type
Humidity,Temperature
Applications
This Click board™ is an ideal solution for development of a
range of different applications, including battery operated
weather stations, thermostats and humidistats,
microenvironment centers, respiratory therapy applications, air
conditioners, and other similar applications.
On-board
modules
SHTC3, a relative humidity and temperature sensor with I²C
Interface, by Sensirion
Key Features
The complete measurement stack on chip, thanks to the
proprietary CMOSens® manufacturing process, advanced logic
back-end offers calibrated data, low drift over time, high
repeatability, etc.
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 Temp&Hum 9 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
+3V3
7
3.3V
5V
10
NC
Ground
GND
8
GND
GND
9
GND
Ground
Onboard settings and indicators
Label
PWR
Name
Default
PWR
-
Description
Power LED indicator
Software support
We provide a library for the Temp&Hum 9 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 contains.
Key functions:
void temphum9_readRegister( uint16_t registerAddress_, uint8_t nData_, uint16_t
*registerBuffer_ ) - reads one or two 16-bit registers.
void temphum9_sendCommand( uint16_t command_ ) - issues (sends) command to device.
void temhum9_getTemperatureAndHumidity( uint8_t mode_, float *measurementData) –
performs temperature and relative humidity measurement and calculates temperature and
relative humidity.
Examples description
The application is composed of three sections :
System Initialization - Initializes LOG and I2C.
Application Initialization - Initializes I2C driver and sends SLEEP and WAKEUP dommands.
Application Task - Performs simultaneous temperature and relative humidity measurements and
logs both values.
void applicationTask( )
{
mikrobus_logWrite( " ", _LOG_LINE );
temhum9_getTemperatureAndHumidity( _TEMPHUM9_NORMAL_MODE, &measurementData[0] );
FloatToStr( measurementData[0], text );
mikrobus_logWrite( "> > > Temperature : ", _LOG_TEXT );
mikrobus_logWrite( text, _LOG_TEXT );
mikrobus_logWrite( " C", _LOG_LINE );
FloatToStr( measurementData[1], text );
mikrobus_logWrite( "> > > Relative humidity : ", _LOG_TEXT );
mikrobus_logWrite( text, _LOG_TEXT );
mikrobus_logWrite( " %", _LOG_LINE );
mikrobus_logWrite( " ", _LOG_LINE );
Delay_ms(1000);
}
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.
https://www.mikroe.com/temphum‐9‐click/2‐13‐19