Environmental Sensor Node SEN5x
All-in-one air quality sensing

Combo sensor module for air quality
measurements
The SEN5x environmental node is a straightforward, all-in-one
sensor solution platform for the accurate measurement of various environmental parameters, such as particulate matter,volatile organic compounds (VOCs), oxidizing gases, such asnitrogen oxide compounds (NOx), as well as humidity andtemperature. Thanks to proprietary algorithms, the module
enables straightforward integration into various applications.
This allows device manufacturers to save valuable projecttime and personnel resources and focus on their core competencies. End customers receive reliable air quality measurement data based on the SEN5x and benefit from improved air quality to increase health and comfort.

Applications:• Air purifiers• Air quality monitors• Air conditioners• HVAC / ventilation systems

STAR engine
When SEN5x is integrated into an end-user product, the resulting thermal behavior can be very complex. A tiny temperature sensor on an unenclosed flex PCB has a negligible thermal mass and couples perfectly to ambient air. It canaccurately measure ambient temperature and will be able to react quickly to changes in temperature. In contrast, abuilt-in sensor module like the SEN5x usually couples weakly to ambient air, has a larger thermal mass and is prone
to additional self-heating due to other heat sources close by. This results in slow reaction times when readingchanges in ambient temperature, typically in the order of 20–25 minutes for typical air quality monitors when theambient temperature changes by 5–10°C.
To improve the reaction time and provide a better
user experience, Sensirion has developed the “Sensirion Temperature Acceleration Routine” (STAR)
engine. This algorithm, which is implemented in theture dynamically and before the end productreaches a thermally stable state. This allows endT(°C)

SEN5x range, estimates the value of the tempera-

users to obtain 2–3x faster and more reliable temperature readings from their products.
The SEN5x offers three pre-defined settings for theSTAR engine to address different design-in situations, covering air purifiers and indoor air quality
monitors.

Time (min)STAR engine

No acceleration

Technology and benefits
TechnologyBenefits

All-in-one environmental node: no co-integration ofFaster time-time-to-market, less R&D expenses,

separate sensor components required

bill of material and assembly costs

Integrated algorithms: temperature and humidity­compensation, VOC/NOx Index calculation
Optimized and tested air flow channel geometry andproven design-in examples
Sheath-flow technology combined with high-quality­components (incl. SHT4x and SGP40)

Reliable and trustworthy measurements
Fast hardware design
Dust-protection and long life-time

Sensor module specifications
Sensor module specifications
Lifetime1> 10 years operating continuously 24h/day

Operating conditions–10 –50 °C

Particulate matter specifications
Mass concentration range

0–1,000 µg/m3

Mass concentration accuracy 2, 3 for PM2.5 4± 5 µg/m3 AND 5% m.v. @ 0–100 µg/m3± 10% m.v. @ 100–1000 µg/m3

Temperature and humidity specifications
Typical accuracy temperature± 0.45 °C @ 15–30 °C, 50 %RH

Typical accuracy relative humidity± 4.5 %RH @ 25 °C, 30–70 %RH

Gas specifications

VOCNOx

Output signals

1–500 VOC Index points

1–500 NOx Index points< ± 15 VOC Index points or<± 50 NOx Index points or % m.v.

% m.v. ­(whichever is larger)­(whichever is larger

Device-to-device variation ⁵, ⁶

Electrical specifications
Supply voltage
Average supply current in measurement-mode(after first 60 seconds)
1
2
3
4
5
6

4.5–5.5 V63 mA

Lifetime is based on mean-time-to-failure (MTTF) calculation. Lifetime might vary depending on different operating conditions.
Also referred to as “between-parts variation” or “device-to-device variation”.
For further details, please refer to the document “Sensirion Particulate Matter Sensor Specification Statement”.
Verification Aerosol for PM2.5 is a 3% atomized KCl solution. Deviation to reference instrument is verified in end-tests for every sensor after calibration.
95% of the sensors will be within the typical tolerance corresponding to 2 assuming a normal distribution for ≥ 100 sensors.
Evaluated using the calibration and test sequence according to the application note SGP41 – Testing Guide.

SEK-SEN5x Evaluation Kit
The SEK-SEN5x evaluation kit has been designed to help
you evaluate Sensirion’s SEN5x environmental nodes
easily and cost-efficiently. The kit contains the SEN5xsensor node, which is equipped with particulate matter
sensing technology, an SGP41, an SHT4x humidity sensor
and a microcontroller featuring VOC and NOx Index, relative humidity and temperature outputs via I²C interface.
The SEK-SEN5x evaluation kit includes two cable sets.
The “adapter cable” allows you to connect to a computer
via the SEK-SensorBridge, which must be bought separately and can be ordered via one of our distribution partners. Sensirion’s SEK-ControlCenter viewer software can beused for evaluating the sensor. In addition, the kit includes a jumper cable that enables fast prototyping, e.g., throughintegration into existing platforms (like Arduino, RaspberryPi, etc.). The software and relevant documentation can be
downloaded from our website.
Learn more: www.sensirion.com/my-sen-ek

Environmental sensing
Environmental conditions have a major impact on our well-being, comfort, and productivity. Sensirion’s sensor solutions
provide detailed and reliable data on key environmental parameters such as humidity, temperature, volatile organic compounds (VOCs), particulate matter (PM2.5), formaldehyde, NOx and CO2. Environmental sensing opens up new possibilities to create smarter devices that improve our comfort and well-being as well as increase energy efficiency in a wide
variety of applications. We accompany you through the entire product development process, from the initial idea to product launch and beyond. Our expertise ranges from prototype construction, design-in support and use-case development
to inline testing at the mass production stage.

www.sensirion.com/sen5x