SGP40

Part: Sensirion SGP40

Type: Indoor Air Quality Sensor for VOC Measurements

Description: The SGP40 is a digital gas sensor for indoor air quality applications, featuring a MOx based sensing element, I2C interface, and a very small 2.44 x 2.44 x 0.85 mm³ 6-pin DFN package with 2.6 mA typical power consumption at 3.3 V.

Operating Conditions:

• Supply voltage: 1.7–3.6 V
• Operating temperature: -10 to 50 °C
• Operating relative humidity: 0 to 90 %RH (non-condensing)
• Max SCL clock frequency: 400 kHz

Absolute Maximum Ratings:

• Max supply voltage: +3.6 V
• Max continuous current: 4.0 mA
• Max junction/storage temperature: +70 °C

Key Specs:

• Output signal (VOC Index): 0–500 VOC Index points
• Output signal (SRAW): 0–65'535 ticks
• Measurement range (Ethanol): 0–1'000 ppm
• Response time (τ63): <10 s (changing concentration)
• Supply voltage (Typ): 3.3 V
• Supply current under operation (Typ): 2.6 mA (at 3.3 V)
• I2C clock frequency (Max): 400 kHz
• Package dimensions: 2.44 x 2.44 x 0.85 mm³

Features:

• MOx based gas sensor for indoor air quality applications
• Outstanding long-term stability and lifetime
• I2C interface with digital output signal
• Temperature-controlled micro hotplate
• Humidity-compensated VOC based indoor air quality signal
• Built-in self-test function

Applications:

• Air purifiers
• Demand-controlled ventilation systems

Package:

• 6-pin DFN (2.44 x 2.44 x 0.85 mm³)

Table 2 lists electrical specifications of the SGP40. Default conditions of 25 °C and 3.3 V supply voltage apply to values in the table below, unless otherwise stated. The SGP40 supports both I 2 C 'standard-mode' and 'fast-mode'. 9

Table 2 Electrical specifications.

Stress levels beyond those listed in Table 5 may cause permanent damage to the device. Exposure to minimum/maximum rating conditions for extended periods may affect sensor performance and reliability of the device.

Table 5 Absolute minimum and maximum ratings.

Gas Sensing Specifications as detailed in Table 1 are guaranteed only when the sensor is stored and operated under the recommended conditions as specified in Table 4 and displayed in Figure 3 and Figure 4 . Prolonged exposure to conditions outside these conditions may reduce sensor performance. The sensor must not be exposed towards condensing conditions ( i.e. , >90 % relative humidity) at any time.

9 http://www.nxp.com/documents/user\_manual/UM10204.pdf

10 Any supply voltage as defined by the min./max. range may be used for continuous operation of the sensor. The typical value specifies the supply voltage at which outgoing quality control is performed.

11 Sending the sgp40_measure_raw command enables continuous operation of the sensor. A 20 % higher current is drawn during 5 ms on VDDH after entering the measurement mode.

Table 4 Recommended humidity and temperature conditions for storing and operating the SGP40. Dew point refers to maximum humidity allowed at minimum and maximum temperature, respectively.

Figure 3 Recommended relative humidity and temperature for operating the SGP40. Green area marks conditions for which humidity compensation has been optimized. Additionally, gray areas mark operating conditions without using the humidity compensation feature.

Table 4 Recommended humidity and temperature conditions for storing and operating the SGP40. Dew point refers to maximum humidity allowed at minimum and maximum temperature, respectively.

Figure 4 Recommended relative humidity and temperature for storing the SGP40.

Figure 3 Recommended relative humidity and temperature for operating the SGP40. Green area marks conditions for which humidity compensation has been optimized. Additionally, gray areas mark operating conditions without using the humidity compensation feature.

To ensure an optimal performance of the SGP40, Handling and Assembly Instructions for SGPxx Gas Sensors as well as the Design-in Guide for Integrating SGP4x Gas Sensors need to be followed.

Figure 12 Package outline drawing of the SGP40. Dimensions are given in millimeters.