HS300x Datasheet

© 2021 Renesas Electronics Corporation

16

April 20, 2021

9. Package Outline Drawings

The package outline drawings are located at the end of this document and are accessible from the Renesas website. The package information

is the most current data available and is subject to change without revision of this document.

10.

Soldering Information

This section discusses soldering considerations for the HS300x. When a relative humidity sensor is exposed to the high heat associated with

the soldering process, the sensor element tends to dry out. To avoid an offset in the relative humidity readings, the sensor element must be

rehydrated after the soldering process. Care must also be taken when selecting the temperatures and durations involved in the soldering

process to avoid irreversibly damaging the sensor element.

The recommended soldering profile for a lead-free (RoHS-compliant) process is shown below.

Figure 21. Recommended Soldering Profile

It is important to ensure this temperature profile is measured at the sensor itself. Measuring the profile at a larger component with a higher

thermal mass means the temperature at the small sensor will be higher than expected.

For manual soldering, the contact time must be limited to 5 seconds with a maximum iron temperature of 350°C.

In either case, a board wash after soldering is not recommended. Therefore, if a solder paste is used, it is strongly recommended that a

“no-clean” solder paste is used to avoid the need to wash the PCB.

After soldering, the recommended rehydration conditions are either:



A relative humidity of 75% RH at room temperature for at least 12 hours



A relative humidity of 40% to 50% RH at room temperature for 3 to 5 days

Otherwise, in the relative humidity readings, there might be an initial offset, which will slowly disappear as the sensor is exposed to ambient

conditions.