SENSIRION SCD4 Series, Manual, Page: 22 / 24

www.sensirion.com Version 1.3 – September 2022 22/24
4.5 Soldering Instructions
For soldering, standard reflow soldering ovens may be used. The sensors are designed to withstand soldering profile based on
IPC/JEDEC J-STD-020 with a maximum peak temperature of 235°C during up to 30 sec for Pb-free assembly in IR/Convection
reflow ovens.
Note that due to the comparably large size of the SCD4x sensor significant temperature differences across the sensor element
can occur during reflow soldering. Specifically, the temperature within the sensor cap can be higher than the temperature
measured at the pad using usual temperature monitoring methods. Care must be taken that a temperature of 235° C is not
exceeded at any time in any part of the sensor.
Do not apply any board wash process step subsequently to the reflow soldering. Note that the dust cover on top of the cap must
not be removed or wetted with any liquid. Finally, the SCD4x is not compatible with vapor phase reflow soldering.
Minor temporary accuracy deviations of the CO
2
reading can result from the reflow soldering of the SCD4x. Full sensor accuracy
is restored after at most five days after the soldering process, independently on whether the sensor is operated or not.
Average ramp-up rate < 3 °C / second
Liquid phase
▪
T
L
▪
t
L
> 220 °C
< 60 seconds
Peak temperature
▪ T
P
▪
t
P
≤ 235 °C
< 30 seconds
Ramp-down rate < 4 °C / seconds for
temperature > T
L
Table 35 Soldering profile parameter
4.6 Traceability
All SCD4x sensors have a distinct electronic serial number for identification and traceability (see chapter 3.9.2). The serial
number can be decoded by Sensirion only and allows for tracking through production, calibration, and testing.
5 Ordering Information
Use the part names and product numbers shown in the following table when ordering the SCD4x CO
2
sensor. For
the latest product information and local distributors, visit http://www.sensirion.com/ .
Part Name Description Ordering quantity (pcs) Product Number
SCD40-D-R2 SCD40 CO2 sensor SMD component as reel, I2C 600 sensors per reel 3.000.521
SCD40-D-R1 SCD40 CO2 sensor SMD component as reel, I2C 60 sensors per reel 3.000.496
SCD41-D-R2 SCD41 CO2 sensor SMD component as reel, I2C 600 sensors per reel 3.000.498
SCD41-D-R1 SCD41 CO2 sensor SMD component as reel, I2C 60 sensors per reel 3.000.497
SEK-SCD41-Sensor SEK-SCD41-Sensor set; SCD41 on development
board with cables 1 3.000.455
SEK-SensorBridge Sensor Bridge to connect SEK-SCD41-Sensor to
computer
1 3.000.124
Table 36 SCD4x ordering options