Datasheet SVM30 Multi-gas, humidity and temperature sensor combo module Measures indoor air quality parameters total VOC (tVOC), CO2-equivalent (CO2eq), relative humidity RH and temperature T Automatic baseline compensation and humidity compensation of MOX gas sensor Outstanding long-term stability and reliability Fully factory calibrated and tested Digital I2C interface 5V supply voltage Dimensions: 39 x 15 x 6.5 mm Product Summary The SVM30 is a Multi-gas, humidity and temperature sensor combo module containing an SGP30 gas sensor as well as an SHTC1 humidity and temperature sensor. The SGP30 gas sensor on the SVM30 combines multiple metal-oxide sensing elements - the pixels - on one chip, thereby offering the possibility to measure a total VOC signal (tVOC) and a CO2 equivalent signal (CO2eq) with one single sensor-chip. The SVM30 further offers calibrated air quality output signals as well as compensation of humidity cross-sensitivity. The sensing element features an unmatched robustness against contamination by siloxanes present in real-world applications enabling a unique long-term stability and low drift. The humidity and temperature sensor on SVM30 covers a humidity measurement range of 0 to 100 %RH and a temperature measurement range of -20 to 85 C with a typical accuracy of 5 %RH and 1C. The gas and RH/T sensor components are designed with Sensirion's CMOSens(R) technology. This technology offers a complete sensor system on a single chip, including the sensing elements, analog and digital signal processing, A/D converter, calibration and data memory and a digital communication interface supporting I2C standard mode. Sensirion's state-of-the-art production process, including full calibration and testing of the sensors, guarantees high reproducibility and reliability. Multi-pixel MOX gas sensor Calibration memory RH sensor Linearization, Baseline compensation, Humidity compensation, Data processing T sensor Linearization, Temperature compensation, Data processing SVM30 Calibration memory I2C interface / ESD protection / Power supply conversion tVOC, CO2eq, RH, T output www.sensirion.com Version 1.1 - March 2019 VDD GND 1/18 Content 1 Gas, humidity and temperature sensor specification 3 1.1 Gas sensing performance 3 1.2 Air Quality Signals 4 1.3 Relative humidity 5 1.4 Temperature 5 1.5 Recommended operating conditions 5 2 Electrical specification 6 2.1 Electrical characteristics 6 2.2 Absolute maximum ratings 6 3 Timing specification 6 3.1 Sensor system timing 6 4 Mechanical specification 7 4.1 Sensor dimensions and mechanical design 7 4.2 Connector specification and pin assignment 7 5 Interface specification 8 6 Operation 9 6.1 Power-Up and Communication Start 9 6.2 Measurement Communication Sequence 9 6.3 Measurement Commands 11 6.4 Soft Reset 13 6.5 Get Serial ID 13 6.6 Checksum Calculation 14 6.7 Conversion of the sensor output for RH and T 14 7 Application description 15 7.1 Typical application diagram 15 7.2 Mounting recommendations 15 8 Quality 16 9 Ordering Information 16 10 Important notices 17 10.1 Warning, personal injury 17 10.2 ESD precautions 17 10.3 Warranty 17 11 Revision history 18 12 Headquarters and subsidiaries 18 www.sensirion.com Version 1.1 - March 2019 2/18 1 Gas, humidity and temperature sensor specification 1.1 Gas sensing performance The values listed in Table 1 are valid at 25C, 50% RH and typical VDD. Parameter Measurement range1 Specified measurement range Signal Values Ethanol signal 0 ppm to 1000 ppm H2 signal 0 ppm to 1000 ppm Ethanol signal 0.3 ppm to 30 ppm H2 signal Ethanol signal 0.5 ppm to 3 ppm see Figure 1 typ.: 15% of meas. value Comments The specifications below are defined for this measurement range2. The specified measurement range covers the gas concentrations expected in indoor air quality applications. Accuracy of the concentration c determined by ln ( ) = Accuracy3,4 H2 signal see Figure 2 typ.: 10% of meas. value Ethanol signal -1.0 H2 signal -1.0 Sensitivity Sensitivity tolerance3 Ethanol signal typ. tolerance: 7% rel. error max. tolerance: 14% rel. error H2 signal typ. tolerance: 7% rel. error max. tolerance: 14% rel. error Ethanol signal see Figure 3 typ.: 1.3% of meas. value H2 signal see Figure 4 typ.: 1.3% of meas. value Long-term drift3, 5 Resolution Sampling frequency Ethanol signal H2 signal Ethanol signal H2 signal 0.2 % of meas. value Max. 40 Hz cref = 0.4 ppm ( - ) a = 512 sout: EthOH/H2 signal output cref = 0.5 ppm at concentration c sref: EthOH/H2 signal output at 0.5 ppm H2 Sensitivity n is defined by - = - ln ( ) 512 The typical numerical value of n is n = -1 for both, the Ethanol and H2 signal. The sensitivity is understood as an average value over the specified measurement range as determined by a least square fit. Change of accuracy over time: Siloxane accelerated lifetime test6 Resolution of Ethanol and H2 signal outputs in relative change of the measured concentration Compare with minimum measurement duration in Table 13 Table 1 Gas sensing performance. 1 Exposure to ethanol and H2 concentrations up to 1000 ppm have been tested. For applications requiring the measurement of higher gas concentrations please contact Sensirion. 2 ppm: parts per million. 1 ppm = 1000 ppb (parts per billion) 3 90% of the sensors will be within the typical accuracy tolerance, >99% are within the maximum tolerance. 4 Valid at an air flow of > 1m/s. 5 The long-term drift is stated as change of accuracy per year of operation. 6 Test conditions: operation in 250 ppm Decamethylcyclopentasiloxane (D5) for 200h simulating 10 years of operation in an indoor environment. www.sensirion.com Version 1.1 - March 2019 3/18 Accuracy ethanol signal Accuracy H2 signal Figure 1 Typical and maximum accuracy tolerance in % of measured value at 25C, 50% RH and typical VDD. The sensors have been operated for at least 24h before the characterization. Figure 2 Typical and maximum accuracy tolerance in % of measured value at 25C, 50% RH and typical VDD. The sensors have been operated for at least 60h before the characterization. Long-term drift Ethanol signal Long-term drift H2 signal Figure 3 Typical and maximum long-term drift in % of measured value at 25C, 50% RH and typical VDD. The sensors have been operated for at least 24h before the first characterization. Figure 4 Typical and maximum long-term drift in % of measured value at 25C, 50% RH and typical VDD. The sensors have been operated for at least 60h before the first characterization. 1.2 Air Quality Signals Parameter Output range Signal TVOC signal Value 0 ppb to 60000 ppb CO2eq signal 400 ppm to 60000 ppm TVOC signal Resolution CO2eq signal Sampling rate 0 ppb - 2008 ppb 2008 ppb - 11110 ppb 11110 ppb - 60000 ppb 400 ppm - 1479 ppm 1479 ppm - 5144 ppm 5144 ppm - 17597 ppm 17597 ppm - 60000 ppm TVOC signal 1 Hz CO2eq signal 1 Hz Comments Maximum possible output range. The gas sensing performance is specified for the measurement range as defined in Table 1 1 ppb 6 ppb 32 ppb 1 ppm 3 ppm 9 ppm 31 ppm The on-chip baseline compensation algorithm has been optimized for this sampling rate. The sensor shows best performance when used with this sampling rate. Table 2 Air quality signal specification www.sensirion.com Version 1.1 - March 2019 4/18 Figure 5 Simplified version of the functional block diagram showing the signal paths of the gas sensor SGP30. 1.3 Relative humidity Parameter Conditions Value Units Accuracy tolerance7 In range of 25 ... 75 %RH and 5 ... 55 C 5.0 %RH Repeatability8 - 0.1 %RH Resolution9 - 0.01 %RH Hysteresis - 1 0 ... 100 %RH s Operating range non-condensing Response time11 63% 8 Typ. <0.25 %RH/y Conditions Value Units In range of 5 ... 55 C Long-term drift12 environment10 %RH Table 3: Humidity sensor specification 1.4 Temperature Parameter - 1 0.1 0.01 -20 ... +85 C Repeatability8 Resolution9 Operating range Long-term drift 13 Typ. <0.02 C/y Accuracy tolerance7 C C C Table 4: Temperature sensor specification 1.5 Recommended operating conditions The sensors show best performance when operated within recommended normal temperature range of 5...55C and absolute humidity range of 4...20 g/m3. Long-term exposure (operated and not operated) to conditions outside the recommended range, especially at high humidity, may affect the sensor performance. Prolonged exposure to extreme conditions may accelerate aging. Furthermore, it may temporarily offset the RH signal (e.g. +3%RH after 60h at >80%RH). After returning into the normal temperature and humidity range the RH-sensor will slowly come back to calibration state by itself. To ensure stable operation of the gas sensor, the conditions described in the document SGP Handling and Assembly Instructions as well as the Infosheet Handling 7 Typical accuracy tolerance according to the document "Sensirion Humidity Sensor Specification Statement". Valid for an air flow of > 1 m/s. The stated repeatability is 3 times the standard deviation (3) of multiple consecutive measurement values at constant conditions and is a measure for the noise on the physical sensor output. 9 Resolution of A/D converter. 10 Condensation shall be avoided because of risk of corrosion and leak currents on the PCB. 11 Time for achieving 63% of a humidity step function, valid at 25C and 1 m/s airflow. Humidity response time in the application depends on the design-in of the sensor. 12 Typical value for operation in normal RH/T operating range. Max. value is < 0.5 %RH/y. Value may be higher in environments with vaporized solvents, out-gassing tapes, adhesives, packaging materials, etc. For more details, please refer to Handling Instructions. 13 Max. value is < 0.04C/y. 8 www.sensirion.com Version 1.1 - March 2019 5/18 Instructions Humidity Sensors regarding exposure to exceptionally high concentrations of some organic or inorganic compounds have to be met, particularly during operation. 2 Electrical specification 2.1 Electrical characteristics Default conditions of 25 C and 5 V supply voltage apply to values in the table below, unless otherwise stated. Parameter Supply voltage Symbol VDD Conditions Min 4.5 Typ. 5 Supply current14 IDD Average - 49 Low level input voltage VIL - High level input voltage VIH - Low level output voltage SDA/SCL load capacitance VOL CL 1.5 mA sink current -0.5 0.7 VDD - Max 5.5 0.4 VDD(max) + 0.5 0.4 200 155 Units V Comments - mA - V - V - V pF - Table 5: Electrical specifications 2.2 Absolute maximum ratings Stress levels beyond those listed in Table 6 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. ESD ratings are for discharge on pins according to IEC 61000-4-2, part 4-2. Parameter Supply voltage, VDD Maximum voltage level at pins SCL, SDA Operating temperature range Rating -0.3 ... +6.5 V -0.3 ... +6.5 V -20 ... +85 C -40 ... +85 C Storage temperature range15 ESD HBM ESD MM 8 kV 200 V Table 6: Absolute maximum ratings. 3 Timing specification 3.1 Sensor system timing Default conditions of 25 C and 5 V supply voltage apply to values the table below, unless otherwise stated. Parameter Symbol Conditions Min. Typ. Max. Units Power-up time tPU After hard reset - 0.4 0.6 ms - 10.8 14.4 ms Measurement duration RH/T tMEAS sensor Measurement duration gas See Table 13 sensor Comments Time between power-up and sensor entering idle state Duration for a humidity and temperature measurement Table 7: Sensor timing specifications. 14 15 A 20% higher current is drawn during 5ms on VDDH after entering the measurement mode of the gas sensor. The recommended storage temperature range is 10-50C. Please consult the Infosheet Handling Instructions Humidity Sensors for more information. www.sensirion.com Version 1.1 - March 2019 6/18 4 Mechanical specification 4.1 Sensor dimensions and mechanical design The physical dimension of SMV30 are shown in Figure 6 and Table 8. L Gas sensor WC W WC RH/T sensor H Figure 6 Top and front view of SVM30 Parameter Length Width Width at constriction Symbol L W WC Height H Max. 39 15 14 6.5 7.2 Units mm mm mm mm mm Comment For product version SVM30-Y For product version SVM30-J Table 8 Mechanical dimensions 4.2 Connector specification and pin assignment The pin assignment is shown in Table 9. Pin 1 2 3 4 Name SCL GND VDD SDA Comment I2C serial clock input Ground (negative supply) Power supply (positive supply) I2C serial data input / output 1 2 3 4 Table 9 Pin assigment SVM30 can be delivered with the connectors listed in Table 10. www.sensirion.com Version 1.1 - March 2019 7/18 Product Version SVM30-Y SVM30-J Connector type Yeonho Electronics, 20037WR-04 Scondar SCT2001WR -S-4P (compatible to JST part no. S4B-PH-SM4-TB) Table 10 Available connector types 5 Interface specification Default conditions of 25 C and 5 V supply voltage apply to the timing of the I2C interface specified in Table 11 and Figure 7. Parameter SCL clock frequency Symbol fSCL Hold time (repeated) START condition tHD;STA LOW period of the SCL clock HIGH period of the SCL clock Set-up time for a repeated START condition SDA hold time SDA set-up time SCL/SDA rise time SCL/SDA fall time SDA valid time Set-up time for STOP condition Capacitive load on bus line tLOW tHIGH tSU;STA tHD;DAT tSU;DAT tR tF tVD;DAT tSU;STO CB Conditions After this period, the first clock pulse is generated - Min. 0 Typ. - Max. 100 Units kHz 4.0 - - s 4.7 4.0 4.7 0 250 4.0 - 1000 300 3.45 400 s s s ns ns ns ns s s pF Table 11 Communication timing specification 1/fSCL tHIGH tR tLOW tF 70% SCL tSU;DAT 30% tHD;DAT DATA IN 70% SDA 30% tVD;DAT DATA OUT SDA tF tR 70% 30% Figure 7 Timing diagram for digital input/output pads. SDA in / out as seen by SVM30. Bold SDA lines are controlled by the sensor; plain SDA lines are controlled by the micro-controller. Note that SDA valid read time is triggered by falling edge of preceding bit. www.sensirion.com Version 1.1 - March 2019 8/18 6 Operation The SVM30 supports I2C standard mode. For detailed information on the I2C protocol, refer to NXP I2C-bus specification. All commands and data are mapped to a 16-bit address space. Additionally, data and commands are protected with a CRC checksum to increase the communication reliability. The 16-bit commands that are sent to the sensor already include a 3-bit CRC checksum. Data sent from and received by SVM30 is always succeeded by an 8-bit CRC. In write direction it is mandatory to transmit the checksum, since SVM30 only accepts data if it is followed by the correct checksum. In read direction it is up to the master to decide if it wants to read and process the checksum. The device addresses of the two sensors on SVM30 are listed in Table 12. Sensor SGP30 SHTC1 Hex. Code 0x58 0x70 Table 12 I2C device addresses of the sensors on SVM30 The typical communication sequence between the I2C master (e.g., a microcontroller in a host device) and the sensor is described as follows: 1. The sensor is powered up, communication is initialized 2. The I2C master periodically requests measurement and reads data, in the following sequence: a. I2C master sends a measurement command b. I2C master waits until the measurement is finished, either by waiting for the maximum execution time or by waiting for the expected duration and then poll data until the read header is acknowledged by the sensor (expected durations are listed in Table 13 and Table 7) c. I2C master reads out the measurement result 6.1 Power-Up and Communication Start After the supply voltage reaching its specified range (see Table 5) the sensor needs the time tPU (see Table 7) to enter the idle state. Once the idle state is entered it is ready to receive commands from the master. Each transmission sequence begins with a START condition (S) and ends with a STOP condition (P) as described in the I2C-bus specification. Please note that in case VDD is set to 0 V (GND), e.g. in case of a power off of SVM30, the SCL and SDA pads are also pulled to GND. Consequently, the I2C bus is blocked while VDD of SVM30 is set to 0 V. 3 4 5 6 I2C adress 7 8 9 W I2C write header 10 11 12 13 14 15 16 Command MSB 17 18 19 20 21 22 23 24 25 Command LSB 26 27 28 ACK S 2 ACK 1 ACK 6.2 Measurement Communication Sequence A measurement communication sequence consists of a START condition, the I2C write header (7-bit I2C device address plus 0 as the write bit) and a 16-bit measurement command (see Figure 8). The proper reception of each byte is indicated by the sensor. It pulls the SDA pin low (ACK bit) after the falling edge of the 8th SCL clock to indicate the reception. With the acknowledgement of the measurement command, SVM30 starts measuring. When the measurement is in progress, no communication with the sensor is possible and the sensor aborts the communication with a XCK condition. P 16-bit command Figure 8 Command access communication sequence. www.sensirion.com Version 1.1 - March 2019 9/18 After the sensor has completed the measurement, the master can read the measurement results by sending a START condition followed by an I2C read header. The sensor will acknowledge the reception of the read header and responds with data. The response data length is listed in Table 13 for SGP30, the one of SHTC1 is 6 bytes incl. checksum. The response data is structured in data words, where one word consists of two bytes of data followed by one byte CRC checksum. Each byte must be acknowledged by the microcontroller with an ACK condition for the sensor to continue sending data. If the sensor does not receive an ACK from the master after any byte of data, it will not continue sending data. After receiving the checksum for the last word of data, an XCK and STOP condition has to be sent. The communication data sequences are shown in Figure 9 for SGP30 and in Figure 10 for SHTC1. 4 5 6 7 8 S 1 1 1 0 0 0 0 0 9 I2C address + write 31 32 33 34 35 11 12 13 14 15 16 17 0 1 0 1 1 1 0 0 Measurement command MSB 36 37 S 1 1 1 0 0 0 0 1 I2C repeated address + read while meas. is in prog. (polling) 18 19 20 21 22 23 24 25 26 0 0 1 0 0 1 0 0 27 28 P Measurement command LSB 38 39 NACK 29 30 10 40 P SHTC1 measuring SHTC1 in idle state measurement cont'd measurement completed 41 42 43 44 45 SHTC1 measuring Measurement in progress 46 47 48 S 1 1 1 0 0 0 0 1 49 ACK 3 ACK 2 ACK 1 ACK Figure 9 Communication sequence for starting a measurement and reading measurement results of SGP30. I2C address + read Humidity MSB Humidity LSB 0 0 0 1 1 1 0 0 ACK 0 0 1 1 0 0 1 1 ACK 1 0 1 0 0 0 0 1 ACK 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 Humidity CRC checksum Temperature MSB Temperature LSB 1 1 0 0 0 1 1 1 ACK 1 0 0 0 1 0 1 1 ACK 0 1 1 0 0 1 0 0 ACK 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 P Temperature CRC checksum Figure 10 Communication sequence for starting a measurement and reading measurement results of SHTC1. The numerical example corresponds to a read humidity-first command with clock stretching enabled. The physical values of the transmitted measurement results are 62.9 %RH and 23.7 C. Clear blocks are controlled by the microcontroller, grey blocks by SHTC1. The I2C master can abort the read transfer with a XCK followed by a STOP condition after any data byte if it is not interested in subsequent data, e.g. the CRC byte or following data bytes, in order to save time. Note that the data cannot be read more than once, and access to data beyond the specified amount will return a pattern of 1's. www.sensirion.com Version 1.1 - March 2019 10/18 6.3 Measurement Commands The available measurement commands of SGP30 are listed in Table 13 and the ones of SHTC1 in Table 14. Feature Set 0x0020 Command Hex. Code Parameter length including CRC [bytes] Response length including CRC [bytes] Measurement duration [ms] Typ. Max. Init_air_quality 0x2003 - - 2 10 Measure_air_quality 0x2008 - 6 10 12 Get_baseline 0x2015 - 6 10 10 Set_baseline 0x201e 6 - 10 10 Set_humidity 0x2061 3 1 10 Measure_test16 0x2032 - 3 200 220 Get_feature_set_version 0x202f - 3 1 2 Measure_raw_signals 0x2050 - 6 20 25 Table 13 Measurement commands of SGP30 Read T first Read RH first 0x7866 0x58E0 Table 14 Measurement commands of SHTC1 SGP30 Air Quality Signals SGP30 uses a dynamic baseline compensation algorithm and on-chip calibration parameters to provide two complementary air quality signals. Based on the sensor signals a total VOC signal (TVOC) and a CO2 equivalent signal (CO2eq) are calculated. Sending an "Init_air_quality" command starts the air quality measurement. After the "Init_air_quality" command, a "Measure_air_quality" command has to be sent in regular intervals of 1s to ensure proper operation of the dynamic baseline compensation algorithm. The sensor responds with 2 data bytes (MSB first) and 1 CRC byte for each of the two preprocessed air quality signals in the order CO 2eq (ppm) and TVOC (ppb). For the first 15s after the "Init_air_quality" command the sensor is in an initialization phase during which a "Measure_air_quality" command returns fixed values of 400 ppm CO2eq and 0 ppb TVOC. A new "Init_air_quality" command has to be sent after every power-up or soft reset. SGP30 Set and Get Baseline The SGP30 also provides the possibility to read and write the baseline values of the baseline compensation algorithm. This feature is used to save the baseline in regular intervals on an external non-volatile memory and restore it after a new power-up or soft reset of the sensor. The command "Get_baseline" returns the baseline values for the two air quality signals. The sensor responds with 2 data bytes (MSB first) and 1 CRC byte for each of the two values in the order CO2eq and TVOC. These two values should be stored on an external memory. After a power-up or soft reset, the baseline of the baseline compensation algorithm can be restored by sending first an "Init_air_quality" command followed by a "Set_baseline" command with the two baseline values as parameters in the order as (TVOC, CO2eq). An example implementation of a generic driver for the baseline algorithm can be found in the document SGP30_driver_integration_guide. SGP30 Raw Signals The command "Measure_raw_signals" is intended for part verification and testing purposes. It returns the sensor raw signals which are used as inputs for the on-chip calibration and baseline compensation algorithms as shown in Figure 5. The command performs a measurement to which the sensor responds with 2 data bytes (MSB first) and 1 CRC byte The Measure_Test command is intended for production line testing and verification only. It should not be used after having issued an "Init_air_quality" command. For the duration of the Measure_Test command, the sensor is operated in measurement mode with a supply current as specified in Table 5. After the command, the sensor is in sleep mode. 16 www.sensirion.com Version 1.1 - March 2019 11/18 (see Figure 9) for 2 sensor raw signals in the order H2_signal (sout_H2) and Ethanol_signal (sout_EthOH). Both signals can be used to calculate gas concentrations c relative to a reference concentration cref by - ln ( ) = with a = 512, sref the H2_signal or Ethanol_signal output at the reference concentration, and sout = sout_H2 or sout = sout_EthOH. SGP30 Humidity Compensation SGP30 features an on-chip humidity compensation for the air quality signals (CO2eq and TVOC) and sensor raw signals (H2-signal and Ethanol_signal). To use the on-chip humidity compensation an absolute humidity value from an external humidity sensor like the SHTxx is required. Using the "Set_humidity" command, a new humidity value can be written to the SGP30 by sending 2 data bytes (MSB first) and 1 CRC byte. The 2 data bytes represent humidity values as a fixedpoint 8.8bit number with a minimum value of 0x0001 (=1/256 g/m3) and a maximum value of 0xFFFF (255 g/m3 + 255/256 g/m3). For instance, sending a value of 0x0F80 corresponds to a humidity value of 15.50 g/m3 (15 g/m3 + 128/256 g/m3). After setting a new humidity value, this value will be used by the on-chip humidity compensation algorithm until a new humidity value is set using the "Set_humidity" command. Restarting the sensor (power-on or soft reset) or sending a value of 0x0000 (= 0 g/m3) sets the humidity value used for compensation to its default value (0x0B92 = 11.57 g/m 3) until a new humidity value is sent. Sending a humidity value of 0x0000 can therefore be used to turn off the humidity compensation. SGP30 Feature Set SGP30 features a versioning system for the available set of measurement commands and on-chip algorithms. This so called feature set version number can be read out by sending a "Get_feature_set_version" command. The sensor responds with 2 data bytes (MSB first) and 1 CRC byte (see Table 15). This feature set version number is used to refer to a corresponding set of available measurement commands as listed in Table 13. Most significant byte (MSB) Bit 1 2 3 4 Product type SGP30: 0 5 6 7 Reserved for future use Least significant byte (LSB) 8 9 10 0 11 12 13 14 15 16 Product version Table 15 Structure of the SGP feature set number. Please note that the last 5 bits of the product version (bits 12-16 of the LSB) are subject to change. This is used to track new features added to the SGP multi-pixel platform. SGP30 Measure Test The command "Measure_test" which is included for integration and production line testing runs an on-chip self-test. In case of a successful self-test the sensor returns the fixed data pattern 0xD400 (with correct CRC). www.sensirion.com Version 1.1 - March 2019 12/18 6.4 Soft Reset SGP30 A sensor reset can be generated using the "General Call" mode according to I2C-bus specification. It is important to understand that a reset generated in this way is not device specific. All devices on the same I 2C bus that support the General Call mode will perform a reset. The appropriate command consists of two bytes and is shown in Table 16. Hex. Code Address byte 0x00 Second byte 0x06 Reset Command using the General Call address 0x0006 2 3 4 5 6 7 8 General Call 1st byte 9 ACK 1 S General Call Address 1 2 3 4 5 6 7 Reset Command 8 9 ACK Command General Call 2nd byte Table 16 Reset of SGP30 through the General Call address (Clear blocks are controlled by the microcontroller, grey blocks by the sensor.). SHTC1 SHTC1 provides a soft reset mechanism that forces the system into a well-defined state without removing the power supply. If the system is in idle state (i.e. if no measurement is in progress) the soft reset command can be sent to SHTC1 according to Figure 8. This triggers the sensor to reset all internal state machines and reload calibration data from the memory. Command Software reset Hex. Code 0x805D Bin. Code 1000'0000'0101'1101 Table 17 Soft reset command for SHTC1 6.5 Get Serial ID SGP30 The readout of the serial ID register can be used to identify the chip and verify the presence of the sensor. The appropriate command structure is shown in Table 18. After issuing the measurement command and sending the ACKbit the sensor needs the time tIDLE = 0.5ms to respond to the I2C read header with an ACK Bit. Hence, it is recommended to wait tIDLE =0.5ms before issuing the read header. The get serial ID command returns 3 words, and every word is followed by an 8-bit CRC checksum. Together the 3 words constitute a unique serial ID with a length of 48 bits. The ID returned with this command are represented in the big endian (or MSB first) format. Command Read ID register Hex. Code 0x3682 Table 18 Get serial ID command of SGP30 SHTC1 SHTC1 has an ID register which contains an SHTC1-specific product code. The read-out of the ID register can be used to verify the presence of the sensor and proper communication. The command to read the ID register is shown in Table 19. Command Read ID register Hex. Code 0xEFC8 Table 19 Get serial ID command of SHTC1 www.sensirion.com Version 1.1 - March 2019 13/18 It needs to be sent to the SHTC1 after an I2C write header. After the SHTC1 has acknowledged the proper reception of the command, the master can send an I2C read header and the SHTC1 will submit the 16-bit ID followed by 8 bits of CRC. The structure of the ID is described in Table 20. 16-bit ID xxxx'xxxx'xx 00'0111 bits 5 to 0: SHTC1-specific product code bits 15 to 6: unspecified information Table 20 Structure of the 16-bit ID of SHTC1. Bits 15:6 of the ID contain unspecified information (marked as "x"), which may vary from sensor to sensor, while bits 5:0 contain the SHTC1-specific product code. 6.6 Checksum Calculation The 8-bit CRC checksum transmitted after each data word is generated by a CRC algorithm. Its properties are displayed in Table 21. The CRC covers the contents of the two previously transmitted data bytes. To calculate the checksum only these two previously transmitted data bytes are used. Property Value Name CRC-8 Width 8 bit Protected Data read and/or write data Polynomial 0x31 (x8 + x5 + x4 + 1) Initialization 0xFF Reflect input False Reflect output False Final XOR 0x00 Examples CRC (0xBEEF) = 0x92 Table 21 I2C CRC properties. 6.7 Conversion of the sensor output for RH and T Measurement data is always transferred as 16-bit values. These values are already linearized and temperature compensated by SHTC1. Humidity and temperature values can be calculated with the formulae given below. Temperature conversion formula (result in C) = -45.68 + 175.7 216 Relative humidity conversion formula (result in %RH) = (103.7 - 3.2 ) 16 16 2 2 SRH and ST denote the 16-bit sensor outputs (as decimal values) for relative humidity and temperature, respectively. www.sensirion.com Version 1.1 - March 2019 14/18 7 Application description 7.1 Typical application diagram A typical application diagram is shown in Figure 11. Because SVM30 already contains pull-up resistors on the I2C lines, the two resistors shown in the typical application diagram are optional. 5V 10 k (optional) 10 k (optional) SCL SVM30 I2C Control Unit SDA Figure 11 Typical application diagram of SVM30 7.2 Mounting recommendations In order to maintain a good contact of the sensors to the environment, it is recommended to mount the module in a place where the sensors have good access to ambient air, if possible in direct airflow. In case there is a fan, it is recommended to mount the module in front of the fan and not behind it, in order to avoid the sensors from measuring the heat generated by the fan. To guarantee best performance of the module it is recommended to obey the air flow directions across the module as depicted by the green and red arrows in Figure 12. In case the module is not placed in an airflow, it is recommended to mount the module such that the RH/T sensor is below the gas sensor in order to avoid heating of the RH/T sensor by the gas sensor through convection. Experiments have shown that heat dissipation from the gas sensor is better if the PCB is mounted upright, rather than when it is mounted flat. To reduce thermal coupling through the substrate the module is mounted on, the substrate should end close to the connector, not reaching the RH/T sensor. air flow Substrate OK Gas sensor air flow air flow Not OK air flow OK (recommended) OK RH/T sensor Figure 12 Recommended direction of incident airflow across the module www.sensirion.com Version 1.1 - March 2019 15/18 8 Quality The qualification of both SGP30 and SHTC1 is performed based on the JEDEC JESD47 qualification test method. Additionally, a separate qualification was performed with the SVM30 module. Visual optical acceptance criteria of the PCB are according to IPC-A-610, class II. 9 Ordering Information The SVM30 can be delivered in 2 versions with different connector types (see Table 10). Ordering numbers see Table 22. Product Version SVM30-J 800 PCS SVM30-J 80 PCS SVM30-Y 800 PCS SVM30-Y 80 PCS Ordering Number 3.000.072 3.000.237 3.000.073 3.000.238 Table 22 Ordering numbers. www.sensirion.com Version 1.1 - March 2019 16/18 10 Important notices 10.1 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. 10.2 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. 10.3 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(c) 2018, by SENSIRION. CMOSens(R) is a trademark of Sensirion All rights reserved www.sensirion.com Version 1.1 - March 2019 17/18 11 Revision history Date Version Page(s) Changes 13. July 2018 01. March 2019 1 1.1 all 16 Initial Release Added order numbers for 80 PCS package 12 Headquarters and subsidiaries Sensirion AG Laubisruetistr. 50 CH-8712 Staefa ZH Switzerland 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.co.kr phone: +41 44 306 40 00 fax: +41 44 306 40 30 info@sensirion.com www.sensirion.com Sensirion Japan Co. Ltd. phone: +81 3 3444 4940 info-jp@sensirion.com www.sensirion.co.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 www.sensirion.com Version 1.1 - March 2019 18/18