Temp-Hum 3 click
PID: MIKROE-2937
Weight: 23 g
Smart environmental temperature and humidity
sensor
Temp-Hum 3 click is a smart environmental temperature and humidity sensor Click
board™, packed with features which allow easy and simple integration into any design that
requires accurate and reliable humidity and temperature measurements. The sensor IC has
integrated sensing elements placed on the bottom of the die, so they are not directly
exposed to the environmental contamination. This translates to a prolonged life of the Click
board™ itself.
Temp-Hum 3 click is a perfect solution for a wide range of applications that depend on
accurate temperature and humidity readings. With its low power consumption and
programmable interrupt requests capability, it is also a perfect choice for various
temperature and relative humidity based IoT applications, such as smart home
applications, smart thermostats, gas sensing, smoke and heat sensors, and similar.
How does it work?
The sensor IC used on the Temp-Hum 3 click is the HDC2010, a Low Power Humidity and
Temperature Digital Sensor from Texas Instruments. This sensor is factory calibrated to
2% relative humidity and 0.2°C temperature accuracy. It has an integrated heating element
that is used to evaporate condensation, protecting the sensor that way. This heating
element can be simply activated by setting a bit in the appropriate register. In the case
when the heater is powered on, the power consumption might rise to about 130mA.
Internally, two sensors are connected to the ADC section, which can be set to sample
measurements with the resolution of 9, 11 or 14 bits, based on the measurement time. The
OTP memory holds the calibration coefficients that are applied to the measured value and
the results are stored on the output registers, in the MSB/LSB format. These values are
then used in formulas found in the HDC2010 datasheet so that the final temperature or
relative humidity data can be calculated. It is also possible to correct the offsets with
custom values.
HDC2010 IC uses the I2C protocol to communicate with the host MCU. Its I2C bus pins are
routed to the mikroBUS™ I2C pins and are pulled to a HIGH logic level by the onboard
resistors. The ADDR pin of the HDC2010 is routed to the CS pin of the mikroBUS™ and it
represents the least significant bit of the I2C address. The final I2C address of this IC is
determined by setting this pin either to a HIGH logic level for 1, or a LOW logic level for 0.
Temp-Hum 3 click supports programmable interrupt engine, saving the host MCU from
having to constantly poll the IC for data. An interrupt signal with a selectable polarity and
behavior can be generated on the DRDY/INT pin of the HDC2010. It can be triggered by
several event sources: it can be triggered by the temperature Lo/Hi threshold events,
Humidity Lo/Hi events, as well as the readiness status of the measurement data. Setting up
the interrupts can be achieved by programming the appropriate IC registers via the I2C
bus. More information about these registers can be found in the HDC2010 datasheet.
HDC2010 IC itself is a very low power consuming device and it can work in two modes:
sleep and active (measurement) mode. The device enters the sleep the mode as soon
possible, to save power. While in the active mode, measurement can be either automatic
with predefined output data rate (ODR) or on-demand. In the automatic mode, the
measurement is triggered in predefined time segments, while on-demand measurement
happens whenever the I2C command is sent. As soon as the single measurement is finished,
the device falls back to a sleep mode.
Onboard SMD jumper is used to select the power supply voltage. This allows Temp-Hum 3
click to be used with both 3.3V and 5V MCUs.
The provided click board™ library contains simple and easy to use functions, which
simplify configuring and reading of the measurement data. These functions are
demonstrated in the included example application and can be used as a reference for
custom projects. These functions can be used in mikroC, mikroBASIC and mikroPASCAL
compilers for all MCU architectures, supported by MikroElektronika.
Specifications
Type
Applications
On-board
modules
Temperature / Humidity
Environmental monitoring, home automation, weather stations, HVAC systems,
wearables, various IoT applications, etc.
HDC2010 Low Power Humidity and Temperature Digital Sensor
The click board measures the relative humidity range from 0% to 100%, it has
Key Features
humidity accuracy of ±2%, and it features an integrated heating element, used to
evaporate condensation, smart sensor IC design, and low power consumption.
Interface
I2C
Input Voltage
3.3V or 5V
Click board
size
S (28.6 x 25.4 mm)
Pinout diagram
This table shows how the pinout on Temp-Hum 3 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
CS
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
+5V
Power Supply
Ground
GND
8
GND
GND
9
GND
Ground
I2C Address LSB
Interrupt output
Temp-Hum 3 click maximum ratings
Description
Min
Typ
Max
Unit
Temperature Accuracy
-0.2
-
2
°C
-2
-
2
% RH
Humidity Accuracy
Operating temperature
-40
-
85
°C
Relative Humidity Operating Range
0
-
100
% RH
I2C clock frequency
10
-
400
kHz
Onboard settings and indicators
Label
Name
Default
JP1
-
Left
LD1
PWR
Description
Power Supply Voltage Selection: Left position 3V3, right
position 5V
PWR indication LED
Software support
We provide a library for Temp-Hum 3 click on our LibStock page, as well as a demo
application (example), developed using MikroElektronika compilers and mikroSDK. The
provided click library is mikroSDK standard compliant. The demo application can run on all
the main MikroElektronika development boards.
Library Description
The library covers all functionalities of the Click board™.
Key functions:
float temphum3_getTemperature() - Reads temperature from sensor
void temphum3_setMeasurement(uint8_t value) - Setup measurement parameters
void temphum3_Configuration(uint8_t value) - Setup sensor configuration
Examples Description
The application is composed of three sections:
•
System Initialization - Initializes I2C module and CS pin as OUTPUT and INT pin as INPUT
•
Application Initialization - Initializes Driver init and settings chip mode ACTIVE and configuration
Measurement and Interrupt, then settings maximum/minimum possible Temperature and
Huminidy.
•
Application Task - (code snippet) - Reads the temperature and huminidy and logs to the USBUART
every 500 ms.
void applicationTask()
{
Temperature = temphum3_getTemperature();
Delay_100ms();
Huminidy = temphum3_getHuminidy();
Delay_100ms();
FloatToStr(Temperature,temp_txt);
mikrobus_logWrite("Temperature : ",_LOG_TEXT);
mikrobus_logWrite(temp_txt,_LOG_LINE);
FloatToStr(Huminidy,hum_txt);
mikrobus_logWrite("Huminidy : ",_LOG_TEXT);
mikrobus_logWrite(hum_txt,_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:
•
I2C
•
UART
•
Conversions
Additional notes and information
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.
Downloads
mikroBUS™ Standard specification
LibStock: mikroSDK
Libstock: Temp-Hum 3 click
HDC2010 datasheet
Temp-Hum 3 click schematic
Temp-Hum 3 click: 2D and 3D files
https://www.mikroe.com/temp-hum-3-click 3-9-18