SEN5X SENSIRION | Alldatasheet
Document overview
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Technical content
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www.sensirion.com Version 2 – D1 – March 2022 2/30 Figure 1 Functional block diagram of the SEN5x. The RH & T and VOC sensors are only contained in the SEN54 and SEN55, the NOx signal is only contained in the SEN55. RH & TVOC & NOxFanFanControllerAmplifier &FilterLaserControllerPowerSupplyAirFlowESDProtectionVDD3V35VPhoto-diodeI2CSDASCLGNDLaserMCU
www.sensirion.com Version 2 – D1 – March 2022 3/30 Content
1 Product Family Overview and Ordering Information 4
2 Environmental Sensor Node Specifications 5
3 Electrical Specifications 11
4 Hardware Interface Specifications 13
5 Functional Overview 14
6 Operation and Communication through the I2C Interface 17
7 Technical Drawings 26
8 Revision History 28
9 Important Notices 29
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1 Product Family Overview and Ordering Information
The SEN5x product family consists of a lineup of sensors with identical dimensions, identical hardware & firmware interface, and varying number of sensor outputs. Table 1 gives an overview of all available product variants with their respective sensor outputs. Specifications and commands for sensor inputs/outputs only apply for the given product if the sensor output is part of this product. Products Sensor outputs Description Article Number SEN50-SDN-T Particulate Matter Particulate matter sensor, tray packaging, 45 pcs. per tray 3.000.667 SEN54-SDN-T Particulate Matter Relative Humidity Temperature VOC Index Environmental sensor node, tray packaging, 45 pcs. per tray 3.000.535 SEN55-SDN-T Particulate Matter Relative Humidity Temperature VOC Index NOx Index Environmental sensor node, tray packaging, 45 pcs. per tray 3.000.593 Table 1: Sensor module specifications.
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2 Environmental Sensor Node Specifications
Default conditions of standard Measurement-Mode (6.1.1), 25 °C and 5 V supply voltage apply to values in the table below, unless otherwise stated.
2.1 Sensor Module Specifications
Parameter Conditions Value Units Sampling interval - 1 0.03 s Lifetime1 24 h/day operation > 10 years Acoustic emission level 0.2 m 24 dB(A) Long term acoustic emission level drift 0.2 m +0.5 dB(A) / year Weight - 36.4 10% g Table 2: Sensor module specifications. 1 Lifetime is based on mean-time-to-failure (MTTF) calculation. Lifetime might vary depending on different operating conditions.
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2.2 Particulate Matter Specifications
Parameter Conditions Value Units Mass concentration specified range - 0 to 1’000 μg/m3 Mass concentration size range PM1.0 0.3 to 1.0 μm PM2.5 0.3 to 2.5 μm PM4 0.3 to 4.0 μm PM10 0.3 to 10.0 μm Mass concentration precision2,3 for PM1 and PM2.54 0 to 100 μg/m3 5 μg/m3 AND 5 % m.v. 100 to 1000 μg/m3 10 % m.v. Mass concentration precision2,3 for PM4, PM105 0 to 100 μg/m3 25 μg/m3 100 to 1000 μg/m3 25 % m.v. Maximum long-term mass concentration precision limit drift 0 to 100 μg/m3 1.25 μg/m3 / year 100 to 1000 μg/m3 1.25 % m.v. / year Typical start-up time6 number concentration 200 – 3000 #/cm3 8 s 100 – 200 #/cm3 16 s 50 – 100 #/cm3 30 s Sensor output characteristics PM2.5 mass concentration Calibrated to TSI DustTrak™ DRX 8533 Ambient Mode Additional T-dependent mass precision limit drift3 temperature difference to 25°C typ. 0.5 % m.v. / °C Laser wavelength (DIN EN 60825-1 Class 1) typ. 660 nm Table 3: Particulate matter sensor specifications. Default conditions of 252 °C, 5010% relative humidity and 5 V supply voltage 2 Also referred to as “between-parts variation” or “device-to-device variation”. 3 For further details, please refer to the document “Sensirion Particulate Matter Sensor Specification Statement”. 4 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. 5 PM4 and PM10 output values are calculated based on distribution profile of all measured particles. 6 Time after starting Measurement-Mode, until a stable measurement is obtained.
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2.3 Temperature and Humidity Specifications
Parameter Conditions Value 7 Units Compensated outputs8 - Temperature and Relative Humidity %RH Typical accuracy temperature @ 15-30 °C, 50 %RH 0.45 °C Max. accuracy temperature @ 15-30 °C, 50 %RH ±0.7 °C Repeatability temperature @ 25 °C, 50 %RH 0.1 °C Response time temperature9 @ 25 °C, 50 %RH, 63% < 60 s Typical accuracy relative humidity @ 25 °C, 30-70 %RH 4.5 %RH Max. accuracy relative humidity @ 25 °C, 30-70 %RH ±6 %RH Repeatability relative humidity @ 25 °C, 50 %RH 1 %RH Response time relative humidity10 @ 25 °C, 50 %RH, 63% < 20 s Table 4: Temperature and humidity specifications. 7 For the definition of the typical and max. accuracy tolerance, please refer to the document “Sensirion Humidity Sensor Specification Statement”. 8 Self-heating of the module is compensated according to the application note “Temperature Acceleration and Compensation Instructions for SEN5x”.
9 For a step from 15°C to 25°C
10 For a step from 75%RH to 25%RH
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2.4 Gas Specifications
Units Min. Typ.11 Max. Output signals VOC Index 1 – 500 VOC Index points NOx Index 1 – 500 NOx Index points Device-to-device variation VOC Index12 – <±15 <±15 – VOC Index points or % VOC Index m.v. (the larger) NOx Index12 – <±50 <±50 – NOx Index points or % NOx Index m.v. (the larger) Repeatability VOC Index12 – <±5 <±5 – VOC Index points or % VOC Index m.v. (the larger) NOx Index12 – <±10 <±10 – NOx Index points or % NOx Index m.v. (the larger) Response time Changing concentration from 5 to 10 ppm of ethanol, at sampling interval of 1 s 63 – <10 – s 90 – <30 – s Switch-on behavior Time until reliably detecting events13 – <60 – s Time until specifications in this table are met VOC Index <1 – h NOx Index <6 – h Table 5: Gas sensing specifications at 25 °C and 50 % RH in zero air (considered as clean air for indoor air quality applications). All concentrations refer to ethanol as test gas. 11 95 % of the sensors will be within the typical tolerance corresponding to 2σ assuming a normal distribution for ≥100 sensors. 12 Evaluated using the calibration and test sequence according to the application note SGP40 – Testing Guide. 13 Signal change during 60-s event of 5000 to 10000 ppb of ethanol or of 100 to 300 ppb of NO2 is three times larger than raw signals drift, without this event during the same duration.
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2.5 Recommended and Absolute Maximum/Minimum Operating and Storage Conditions
The SEN5x contains different sensing components with different recommended operating and storage ranges. To ensure an optimal performance of the SEN5x, the “SEN5x Handling Instructions” as well as the “SEN5x Mechanical Assembly and Design-in Guidelines” need to be followed.
2.5.1 SEN54 and SEN55
Table 6 and Figure 2 show the recommended operating and storage conditions in which all the sensing components of the SEN54 and SEN55 show best performance, as well as absolute maximum/minimum conditions which must not be exceeded. Gas sensing specifications are guaranteed only when the SEN54 and SEN55 are operated and stored under the recommended conditions given in Table 6. Exposure to conditions outside the recommended range may temporarily reduce sensor performance (reversible RH drift, reduced RH, T, gas, PM accuracy). Exposure to conditions outside absolute maximum/minimum range may lead to permanently reduced sensor performance (gas sensitivity drift) or cause permanent damage to the device. The sensor must not be exposed towards condensing conditions at any time. Condition Parameter Recommended Absolute Maximum/Minimum Unit Min. Max. Min. Max. Operating conditions Temperature 10 40 -10 50 °C Relative humidity 20 80 0 90 (non-condensing) % RH Storage conditions Temperature 10 30 -40 70 °C Relative Humidity 20 60 0 80 (non-condensing) % RH Table 6 Recommended and absolute maximum/minimum operating and storage conditions for SEN54 and SEN55. Figure 2 Recommended and absolute maximum/minimum operating and storage conditions for SEN54 and SEN55. Operating020406080100Relative humidity / %-400 40 80-20 2060Temperature / °C020406080100Relative humidity / %-40Storage0 40 80-20 2060Temperature / °CRecommended rangeAbsolute maximum/minimum range
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3 Electrical Specifications
3.1 Electrical Characteristics
Parameter Conditions Min Typ Max Unit Supply voltage - 4.5 5.0 5.5 V Sensor startup time (Time after power-on until I2C communication can be started) - - 50 ms Average supply current Idle Mode (first 10 seconds) SEN55 - 3.8 4.2 mA SEN54 - 0.7 1 SEN50 - 0.7 1 Idle Mode (after first 10 seconds) SEN55 - 2.6 3 SEN54 - 0.7 1 SEN50 - 0.7 1 RHT/Gas-only Measurement Mode SEN55 - 6.8 8 SEN54 - 6.5 7.7 Measurement-Mode (first 60 seconds) SEN55 - 70 100 SEN54 - 70 100 SEN50 - 70 100 Measurement-Mode (after first 60 seconds) SEN55 - 63 80 SEN54 - 63 80 SEN50 - 63 80 Peak supply current Measurement mode (pulse width of 16µs) - 100 110 mA Input high level voltage (VIH) - 2.31 - 5.5 V Input low level voltage (VIL) - 0 - 0.99 Output low level voltage (VOL) Sink current <6mA 0 0 0.4 Table 8 Electrical specifications at 25°C.
3.2 Absolute Maximum Ratings
Stress levels beyond those listed in Table 9 may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these conditions cannot be guaranteed. Exposure to the absolute maximum rating conditions for extended periods may affect the reliability of the device. Parameter Min Max Unit Supply voltage VDD -0.3 5.5 V Interface Select SEL -0.3 5.5 I/O pins (RX/SDA, TX/SCL) -0.3 5.5 Max. current on any I/O pin -16 16 mA Operating temperature range see Table 6 Operating humidity range see Table 6 Storage temperature range (short-term, e.g. transport) see Table 6 Storage humidity range (short-term, e.g. transport) see Table 6 Table 9: Absolute minimum and maximum ratings.
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3.3 ESD / EMC Ratings
Description Standard Rating Electro Static Discharge IEC 61000-4-2 ±4 kV contact, ±8 kV air Power-Frequency Magnetic Field IEC 61000-4-8 30A/m, 50Hz and 60Hz Radio-Frequency EM-Field AM-modulated IEC 61000-4-3 80MHz - 1000MHz, 3V/m, 80% AM @1kHz Radio-Frequency EM-Field AM-modulated IEC 61000-4-3 1.4GHz – 6GHz, 3V/m, 80% AM @1kHz Emission Description Standard Rating Emission in SAC for 30MHz to 230MHz IEC/CISPR 16 40dB(µV/m) QP @3m Emission in SAC for 230MHz to 1000MHz IEC/CISPR 16 47dB(µV/m) QP @3m
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5.2 Fan Auto Cleaning
When the module is in Measurement-Mode an automatic fan-cleaning procedure will be triggered periodically following a defined cleaning interval. This will accelerate the fan to maximum speed for 10 seconds to blow out the accumulated dust inside the fan. Measurement values are not updated while the fan-cleaning is running. The cleaning interval is set to 604’800 seconds (i.e., 168 hours or 1 week) with a tolerance of 3%. The interval can be configured using the Set Automatic Cleaning Interval command. Set the interval to 0 to disable the automatic cleaning. A sensor reset, resets the cleaning interval to its default value If the sensor is switched off, the time counter is reset to 0. Make sure to trigger a cleaning cycle at least every week if the sensor is switched off and on periodically (e.g., once per day). The cleaning procedure can also be started manually with the Start Cleaning command.
5.3 Temperature compensation
By default, the temperature and humidity outputs from the sensor are compensated for the modules self-heating. If the module is designed into a device, the temperature compensation might need to be adapted to incorporate the change in thermal coupling and self-heating of other device components. A guide to achieve optimal performance, including references to mechanical design-in examples can be found in the app note “Temperature Acceleration and Compensation Instructions for SEN5x” at www.sensirion.com.
5.4 Device Status Register
The Device Status Register is a 32-bit register that contains information about the internal state of the module. 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 Warning Info 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Error Error Error Error SENSOR RHT LASER FAN res. res. res. res. Note: All “res.” bits are reserved for internal use or future versions. These bits can be both 0 and 1 and should therefore be ignored. Bit 21 SPEED: Fan speed out of range 0: Fan speed is ok. 1: Fan speed is too high or too low. During the first 3 seconds after starting the measurement (fan start-up) the fan speed is not checked. The fan speed is also not checked during the auto cleaning procedure. Apart from the two exceptions mentioned above, the fan speed is checked once per second in the measurement mode. If it is out of range twice in succession, the SPEED-bit is set. At very high or low ambient temperatures, the fan may take longer to reach its target speed after start-up. In this case, the bit will be set. As soon as the target speed is reached, this bit is cleared automatically. If this bit is constantly set, this indicates a problem with the power supply or that the fan is no longer working properly
www.sensirion.com Version 2 – D1 – March 2022 16/30 Bit 19 FAN: Fan cleaning active 0: Fan is running normal. 1: Active during the automatic cleaning procedure of the fan Bit 7 GAS SENSOR: Gas sensor error (VOC & NOx) 0: Gas sensor is running normal. 1: Gas sensor error Bit 6 RHT: RHT communication error 0: RHT sensor is running normal. 1: Error in internal communication with the RHT sensor Bit 5 LASER: Laser failure 0: Laser current is ok. 1: Laser is switched on and current is out of range. The laser current is checked once per second in the measurement mode. If it is out of range, the LASER-bit is set. If the laser current is back within limits, this bit will be not cleared automatically. A laser failure can occur at very high temperatures outside of specifications or when the laser module is defective. Bit 4 FAN: Fan failure, fan is mechanically blocked or broken. 0: Fan works as expected. 1: Fan is switched on, but the measured fan speed is 0 RPM. The fan is checked once per second in the measurement mode. If 0 RPM is measured twice in succession, the FAN bit is set. The FAN-bit will not be cleared automatically. A fan failure can occur if the fan is mechanically blocked or broken.
www.sensirion.com Version 2 – D1 – March 2022 17/30 uint8_t CalcCrc(uint8_t data[2]) { uint8_t crc = 0xFF; for(int i = 0; i < 2; i++) { crc ^= data[i]; for(uint8_t bit = 8; bit > 0; --bit) { if(crc & 0x80) { crc = (crc << 1) ^ 0x31u; } else { crc = (crc << 1); } } } return crc; }
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6.1 I2C Commands
The following table shows an overview of the available I2C commands. Address Pointer Command Name Communication Command execution time 0x0021 Start Measurement Write Data < 50 ms 0x0037 Start Measurement in RHT/Gas-Only Measurement Mode Write Data < 50 ms 0x0104 Stop Measurement Write Data < 200 ms 0x0202 Read Data-Ready Flag Read/ Write Data < 20 ms 0x03C4 Read Measured Values Read/ Write Data < 20 ms 0x60B2 Read/ Write Temperature Compensation Parameters Read/ Write Data and Parameters < 20 ms 0x60C6 Read/ Write Warm Start Parameters Read/ Write Data and Parameters < 20 ms 0x60D0 Read/Write VOC Algorithm Tuning Parameters Read/ Write Data and Parameters < 20 ms 0x60E1 Read/Write NOx Algorithm Tuning Parameters Read/ Write Data and Parameters < 20 ms 0x60F7 Read/Write RH/T Acceleration Mode Read/ Write Data and Parameters < 20 ms 0x6181 Read/Write VOC Algorithm State Read/ Write Data and Parameters < 20 ms 0x5607 Start Fan Cleaning Write Data < 20 ms 0x8004 Read/Write Auto Cleaning Interval Read/ Write Data and Parameters < 20 ms 0xD014 Read Product Name Read/ Write Data < 20 ms 0xD033 Read Serial Number Read/ Write Data < 20 ms 0xD100 Read Firmware Version Read/ Write Data < 20 ms 0xD206 Read Device Status Read/ Write Data < 20 ms 0xD210 Clear Device Status Write Data < 20 ms 0xD304 Reset Write Data < 100 ms Table 12: Reference table for I2C commands. Please note that all commands are volatile.
6.1.1 Start Measurement (0x0021)
Starts the measurement. After power up, the module is in Idle-Mode. Before any measurement values can be read, the Measurement-Mode needs to be started using this command.
6.1.2 Start Measurement in RHT/Gas-Only Measurement Mode (0x0037)
Starts a continuous measurement without PM. Only humidity, temperature, VOC, and NOx are available in this mode. Laser and fan are switched off to keep power consumption low.
6.1.3 Stop Measurement (0x0104)
Stops the measurement. Use this command to return to the initial state (Idle-Mode).
6.1.4 Read Data-Ready Flag (0x0202)
This command can be used for polling to find out when new measurements are available.
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1 Data-Ready Flag
0x00: no new measurements available 0x01: new measurements ready to read
2 Checksum for bytes 0, 1
6.1.5 Read Measured Values (0x03C4)
Reads the measured values from the sensor module and resets the “Data-Ready Flag”. If the sensor module is in Measurement-Mode, an updated measurement value is provided every second and the “Data-Ready Flag” is set. If no synchronized readout is desired, the “Data-Ready Flag” can be ignored. The command “Read Measured Values” always returns the latest measured values. After sending the “Read Measured Values” command, a wait time of 10 ms is needed so that the sensor internally can fill the data buffers. After 20 ms, the read data header can be sent to read out the sensor data. In RHT/Gas-Only Measurement Mode, the PM output is 0xFFFF. If any value is unknown, 0xFFFF is returned. Command Returned data 0x03C4 PM Mass concentration, Relative humidity, Temperature, VOC Index, NOx Index Read/Write Data: Byte # Datatype Scale factor Description 0..1 big-endian, uint16 10 Mass Concentration PM1.0 [µg/m³] 3..4 big-endian, uint16 10 Mass Concentration PM2.5 [µg/m³]
5 Checksum for bytes 3, 4
6..7 big-endian, uint16 10 Mass Concentration PM4.0 [µg/m³]
8 Checksum for bytes 6, 7
9..10 big-endian, uint16 10 Mass Concentration PM10 [µg/m³]
11 Checksum for bytes 9, 10
12..13 big-endian, int16 100 Compensated Ambient Humidity [%RH]
14 Checksum for bytes 12, 13
15..16 big-endian, int16 200 Compensated Ambient Temperature [°C]
17 Checksum for bytes 15, 16
18..19 big-endian, int16 10 VOC Index
20 Checksum for bytes 18, 19
21..22 big-endian, int16 10 NOx Index
23 Checksum for bytes 21, 22
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6.1.6 Read/ Write Temperature Compensation Parameters (0x60B2)
These commands allow to compensate temperature effects of the design-in at customer side by applying a custom temperature offset to the ambient temperature. The compensated ambient temperature is calculated as follows: T_Ambient_Compensated = T_Ambient + (slope*T_Ambient) + offset Where slope and offset are the values set with this command, smoothed with the specified time constant. The time constant is how fast the slope and offset are applied. After the specified value in seconds, 63% of the new slope and offset are applied. More details about the tuning of these parameters are included in the application note “Temperature Acceleration and Compensation Instructions for SEN5x”. All temperatures (T_Ambient_Compensated,T_Ambient and offset) are represented in °C. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 big-endian, int16 200 Temperature offset [°C] (default value: 0) 3..4 big-endian, int16 10000 Normalized temperature offset slope (default value: 0) 6..7 big-endian, uint16 1 Time constant in seconds (default value: 0)
6.1.7 Read/ Write Warm Start Parameter (0x60C6)
The temperature compensation algorithm is optimized for a cold start by default, i.e., it is assumed that the "Start Measurement" commands are called on a device not yet warmed up by previous measurements. If the measurement is started on a device that is already warmed up, this parameter can be used to improve the initial accuracy of the ambient temperature output. This parameter can be gotten and set in any state of the device, but it is applied only the next time starting a measurement, i.e., when sending a "Start Measurement" command. So, the parameter needs to be written before a warm-start measurement is started. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 big-endian, uint16 1 Warm start behavior as a value in the range from 0 (cold start, default value) to 65535 (warm start). (default value: 0)
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6.1.8 Read/ Write VOC Algorithm Tuning Parameters (0x60D0)
The VOC algorithm can be customized by tuning 6 different parameters. More details on the tuning instructions are provided in the application note “Engineering Guidelines for SEN5x”. Note that this command is available only in idle mode. In measure mode, this command has no effect. In addition, it has no effect if at least one parameter is outside the specified range. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 big-endian, int16 1 Index Offset VOC index representing typical (average) conditions. Allowed values are in range 1..250. The default value is 100. 3..4 big-endian, int16 1 Learning Time Offset Hours Time constant to estimate the VOC algorithm offset from the history in hours. Past events will be forgotten after about twice the learning time. Allowed values are in range 1..1000. The default value is 12 hours. 6..7 big-endian, int16 1 Learning Time Gain Hours Time constant to estimate the VOC algorithm gain from the history in hours. Past events will be forgotten after about twice the learning time. Allowed values are in range 1..1000. The default value is 12 hours. 9..10 big-endian, int16 1 Gating Max Duration Minutes Maximum duration of gating in minutes (freeze of estimator during high VOC index signal). Zero disables the gating. Allowed values are in range 0..3000. The default value is 180 minutes. 12..13 big-endian, int16 1 Std Initial Initial estimate for standard deviation. Lower value boosts events during initial learning period, but may result in larger device-to- device variations. Allowed values are in range 10..5000. The default value is 50. 15..16 big-endian, int16 1 Gain Factor Gain factor to amplify or to attenuate the VOC index output. Allowed values are in range 1..1000. The default value is 230.
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6.1.9 Read/ Write NOx Algorithm Tuning Parameters (0x60E1)
The NOx algorithm can be customized by tuning 6 different parameters. More details on the tuning instructions are provided in the application note “Engineering Guidelines for SEN5x”. This command is available only in idle mode. In measure mode, this command has no effect. In addition, it has no effect if at least one parameter is outside the specified range. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 big-endian, int16 1 Index Offset NOx index representing typical (average) conditions. Allowed values are in range 1..250. The default value is 1. 3..4 big-endian, int16 1 Learning Time Offset Hours Time constant to estimate the NOx algorithm offset from the history in hours. Past events will be forgotten after about twice the learning time. Allowed values are in range 1..1000. The default value is 12 hours. 6..7 big-endian, int16 1 Learning Time Gain Hours The time constant to estimate the NOx algorithm gain from the history has no impact for NOx. This parameter is still in place for consistency reasons with the VOC tuning parameters command. This parameter must always be set to 12 hours. 9..10 big-endian, int16 1 Gating Max Duration Minutes Maximum duration of gating in minutes (freeze of estimator during high NOx index signal). Set to zero to disable the gating. Allowed values are in range 0..3000. The default value is 720 minutes. 12..13 big-endian, int16 1 Std Initial The initial estimate for standard deviation parameter has no impact for NOx. This parameter is still in place for consistency reasons with the VOC tuning parameters command. This parameter must always be set to 50.
14 Checksum for bytes 12,
15..16 big-endian, int16 1 Gain Factor Gain factor to amplify or to attenuate the NOx index output. Allowed values are in range 1..1000. The default value is 230.
17 Checksum for bytes 15,
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6.1.10 Read/ Write RH/T Acceleration Mode (0x60F7)
By default, the RH/T acceleration algorithm is optimized for a sensor which is positioned in free air. If the sensor is integrated into another device, the ambient RH/T output values might not be optimal due to different thermal behavior. This parameter can be used to adapt the RH/T acceleration behavior for the actual use-case, leading in an improvement of the ambient RH/T output accuracy. There is a limited set of different modes available, each identified by a number:
- 0: Low Acceleration
- 1: High Acceleration
- 2: Medium Acceleration Medium and high accelerations are particularly indicated for air quality monitors which are subjected to large temperature changes. Low acceleration is advised for stationary devices not subject to large variations in temperature. This parameter can be changed in any state of the device, but it is applied only the next time starting a measurement, i.e., when sending a "Start Measurement" command. So, the parameter needs to be set before a new measurement is started. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 big-endian, uint16 1 RH/T acceleration mode.
6.1.11 Read/ Write VOC Algorithm State (0x6181)
Allows to backup and restore the VOC algorithm state to resume operation after a short interruption, skipping initial learning phase. By default, the VOC algorithm resets its state to initial values each time a measurement is started, even if the measurement was stopped only for a short time. So, the VOC index output value needs a long time until it is stable again. This can be avoided by restoring the previously memorized algorithm state before starting the measure mode. Read/Write Data and Parameters: Byte # Datatype Scale factor Description 0..1 Bytearray8 1 VOC algorithm state. 9..10 Bytearray8 1
6.1.12 Start Fan Cleaning (0x5607)
Starts the fan-cleaning manually. This command can only be executed in Measurement-Mode. For more details, note the explanations given in 5.2 Fan Auto Cleaning.
6.1.13 Read/Write Auto Cleaning Interval (0x8004)
Reads/Writes the interval [s] of the periodic fan-cleaning. For more details, note the explanations given in 5.2 Fan Auto Cleaning. Please note that since this configuration is volatile, it will be reverted to the default value after a device reset.
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6.1.14 Read Product Name (0xD014)
This command returns the product name SEN5x (SEN50, SEN54 or SEN55). It is defined as a string value with a maximum length of 32 ASCII characters (including terminating null-character). Read/Write Data: Byte # Description
0 ASCII Character 0
1 ASCII Character 1
… …
45 ASCII Character 30
46 ASCII Character 31
47 Checksum for bytes 45, 46
6.1.15 Read Serial Number (0xD033)
This command returns the requested serial number. It is defined as a string value with a maximum length of 32 ASCII characters (including terminating null-character). Read/Write Data: Byte # Description … …
6.1.16 Read Firmware Version (0xD100)
Get firmware version. Read/Write Data: Byte # Description
0 Firmware version
1 Reserved
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6.1.17 Read Device Status (0xD206)
Use this command to read the Device Status Register. For more details, note the explanations given in section 5.4 Device Status Register. Read/Write Data: Byte # Description 0, 1 Most Significant Byte big-endian, unsigned 32-bit integer value: Device Status Register 2 Checksum for bytes 0, 1 3, 4 Least Significant Byte
6.1.18 Clear Device Status (0xD210)
Clears all flags in device status register.
6.1.19 Device Reset (0xD304)
Device software reset command. After calling this command, the module is in the same state as after a power reset.
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7 Technical Drawings
7.1 Product outline drawings
Figure 7: Package outline dimensions (given in mm) of the SEN5x.
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7.2 Product Label
The SEN5x contains a label (size: 18 x 12 mm) which is attached to one side of the sensor and contains the following information: Label Design Label Content Description SEN5x Product name SDN-T Sensirion internal marking xxxxxxxxxxxxxxxx / S 16-digit decimal serial number Table 13 Label information. Figure 8: Indication of label position on SEN5x. label position
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8 Revision History
Date Version Page(s) Changes January 2022 1 - Initial version March 2022 2 4 9-10 Updated table Added Recommended and Absolute Maximum/Minimum Operating and Storage Conditions for SEN55 and SEN50 Updated flowchart and description of operating modes Updated names for the RH/T Acceleration Mode parameters
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9 Important Notices
Warning, Personal Injury Do not use this product as safety or emergency stop devices or in any other application where failure of the product could result in personal injury. Do not use this product for applications other than its intended and authorized use. Before installing, handling, using or servicing this product, please consult the data sheet and application notes. Failure to comply with these instructions could result in death or serious injury. If the Buyer shall purchase or use SENSIRION products for any unintended or unauthorized application, Buyer shall defend, indemnify and hold harmless SENSIRION and its officers, employees, subsidiaries, affiliates and distributors against all claims, costs, damages and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if SENSIRION shall be allegedly negligent with respect to the design or the manufacture of the product. ESD Precautions The inherent design of this component causes it to be sensitive to electrostatic discharge (ESD). To prevent ESD- induced damage and/or degradation, take customary and statutory ESD precautions when handling this product. See application note “ESD, Latchup and EMC” for more information. Warranty SENSIRION warrants solely to the original purchaser of this product for a period of 12 months (one year) from the date of delivery that this product shall be of the quality, material and workmanship defined in SENSIRION’s published specifications of the product. Within such period, if proven to be defective, SENSIRION shall repair and/or replace this product, in SENSIRION’s discretion, free of charge to the Buyer, provided that: notice in writing describing the defects shall be given to SENSIRION within fourteen (14) days after their appearance; such defects shall be found, to SENSIRION’s reasonable satisfaction, to have arisen from SENSIRION’s faulty design, material, or workmanship; the defective product shall be returned to SENSIRION’s factory at the Buyer’s expense; and the warranty period for any repaired or replaced product shall be limited to the unexpired portion of the original period. This warranty does not apply to any equipment which has not been installed and used within the specifications recommended by SENSIRION for the intended and proper use of the equipment. EXCEPT FOR THE WARRANTIES EXPRESSLY SET FORTH HEREIN, SENSIRION MAKES NO WARRANTIES, EITHER EXPRESS OR IMPLIED, WITH RESPECT TO THE PRODUCT. ANY AND ALL WARRANTIES, INCLUDING WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE EXPRESSLY EXCLUDED AND DECLINED. SENSIRION is only liable for defects of this product arising under the conditions of operation provided for in the data sheet and proper use of the goods. SENSIRION explicitly disclaims all warranties, express or implied, for any period during which the goods are operated or stored not in accordance with the technical specifications. SENSIRION does not assume any liability arising out of any application or use of any product or circuit and specifically disclaims any and all liability, including without limitation consequential or incidental damages. All operating parameters, including without limitation recommended parameters, must be validated for each customer’s applications by customer’s technical experts. Recommended parameters can and do vary in different applications. SENSIRION reserves the right, without further notice, (i) to change the product specifications and/or the information in this document and (ii) to improve reliability, functions and design of this product. Copyright © 2021, by SENSIRION. CMOSens® is a trademark of Sensirion. All rights reserved
www.sensirion.com Version 2 – D1 – March 2022 30/30 Headquarters and Subsidiaries Sensirion AG Laubisruetistr. 50 CH-8712 Staefa ZH Switzerland phone: +41 44 306 40 00 fax: +41 44 306 40 30 info@sensirion.com www.sensirion.com Sensirion Inc., USA phone: +1 312 690 5858 info-us@sensirion.com www.sensirion.com Sensirion Korea Co. Ltd. phone: +82 31 337 7700~3 info-kr@sensirion.com www.sensirion.com/kr Sensirion Japan Co. Ltd. phone: +81 3 3444 4940 info-jp@sensirion.com www.sensirion.com/jp Sensirion China Co. Ltd. phone: +86 755 8252 1501 info-cn@sensirion.com www.sensirion.com/cn Sensirion Taiwan Co. Ltd phone: +886 3 5506701 info@sensirion.com www.sensirion.com To find your local representative, please visit www.sensirion.com/distributors