New sensors Sensirion will take you only 3x3mm on PCB!
Calibrated humidity and temperature sensors Sensirion SHT21, SHT25 and STS21 excel by very small dimensions. Thanks to their miniature size and a very low power consumption, you can use them even in small portable devices.
Sensors SHT21, SHT25 and STS21 with I2C digital output belong to the
SHT
product line, with the CMOSens technology of swiss company Sensirion. SHT21 and
SHT25 measure relative humdity and temperature, STS21 measure only temperature.
With a new CMOSens chip, reworked capacitive type humidity sensor and the
improved band-gap temperature sensor they feature excellent properties. They
have very similar and in some aspects even better properties than
SHT1x and
SHT7x sensors. Also these sensors belong to high quality CMOS sensors, which
contain all elements of the measuring chain on one chip: humidity and
temperature sensor, precise supply, low noise linear amplifier, AD converter and
interface. Inspite of very compact dimensions also SHT21 and 25 sensors remain
resolution of 12 bits for relative humidity and 14 bits for temperature.
Temperature sensor STS21 has also a 14 bit resolution and a user can choose by a
command the resolution of 14, 13, 12 or 11 bits.
Advantages / Features:
- relative humidity and temperature measurment in one component
- individually calibrated in a precise humidity chamber
- extremely compact dimensions 3 x 3 x 1,1 mm
- digital outpt with I2C interface (Hold/No Hold Master)
- outstanding reliability and long-term stability
- 12 bit resolution for relative humidity and 14 bits for temperature
- measuring range 0-100% RH,-40 to +125 °C
- average consumption only 3.2 uW at 1 measurement per sec/8 bit/RH
(SHT2x)
- average consumption only 3.2 uW at 1 measurement per sec/11 bit/Temp.
(STS21)
- insensitivity to external disturbances (EMC)
- SMT package DFN3-0, reflow solderable
I2C interface enables a very simple communication with a host
microcontroller, in a Hold/ No Hold Master mode. Defaultly sensors have the same
I2C adress set from production. Upon request it is possible to provide sensors
with various adresses from producer. STS21 is fully compatible with SHT2x but it
has a different I2C address. This enables to use sensor STS21 in applications
where humidity measurment is optional and enables to use the same hardware.
In regard to a fact that these sensors are calibrated from production, they
are suitable for very precise temperature and relative humidity measurments, or
also a dew point calculation. In comparison to SHT21, SHT25 has a higher
accuracy and it is suitable even for very demanding applications. Moreover SHT25
keeps its outstanding accuracy of relative humidity measurment also in a wide
temperature range. STS21 offers excellent accuracy of temperature measurment at
a very competitive price.
Price of these sensors is very affordable, when we realize, that these
sensors represent a complete calibrated solution with the digital output, high
reliability and a long life. Besides a direct costs saving, with the Sensirion
sensors you gain also an essential shortening of development time in comparison
to a solution from discrete components. In the DFN package with dimensions only
3,0 x 3,0 x 1,1mm they belong to the world-wide smallest complete solutions for
humidity and temperature measurment in one component.
It is possible to use the
SF2 filter for protection of the sensor against dirt
and droplets. Detailed information will provide you the
SHT21,
SHT25 and
STS21
datasheets. For development support also
EK-H4 and
EK-H5 evaluation kits are
available.
201111040528.11.2011ComponentsSOS electronic s.r.o.