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Version 0.8 – January 2017

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7.

Soldering

Recommended land pattern

The solder mask is understood to be the insulating layer on top of the PCB covering the copper traces. It is recommended to

design the land pattern as a Non- Solder Mask Defined (NSMD) type.

Recommended stencil aperture

The sensor must enter the reflow process only once, with a minimal temperature and exposure time. When both sides of the

PCB are reflow soldered or multiple reflow runs are required, the sensor must be soldered in the last soldering run. In any

case the temperature should not exceed 260°C; temperatures above 200°C should be limited in time to a maximum of 150

seconds.

Ensure that the ports of the sensor are well protected during assembly and soldering so that no dust, solder flux or other

liquids can enter the flow channel. In no case, a board wash shall be applied. Therefore it is strongly recommended to use “no-

clean” solder paste.

It is important to note that the diced edge or side faces of the I/O pads may oxidize over time, therefore a solder fillet may or

may not form. Hence there is no guarantee for solder joint fillet heights of any kind.

Refer to the SDP3x handling instructions on our website for more details.