In high-density test systems, space matters. Engineers are often trying to fit more channels into smaller PCB areas, while still maintaining signal integrity, measurement accuracy and long-term reliability.
This is where compact reed relays, such as Pickering’s 3.9 mm Series 120, can offer significant advantages. Intended for use on 4 mm pitch layouts, the Series 120 allows relays to be closely stacked while retaining the benefits of reed relay switching, including high insulation resistance, low leakage, low contact resistance and long operating life.
However, physical size is only part of the decision. When relays are used in precision measurement systems, the way they behave electrically can be just as important as the footprint they occupy.
A relay may appear similar in size, layout or contact form, but that does not mean it will deliver the same performance in the signal path.
Compact switching without compromising measurement stability
Thermal EMF is a small voltage generated when temperature differences occur between dissimilar conductive materials in a circuit. In many applications, this voltage may be too small to matter. But in low-level measurement systems, microvolt-level offsets can become a meaningful source of error.
This is especially relevant in compact relay designs. As components become smaller and test systems become more densely packed, engineers need to be confident that the relay is not introducing unwanted offset or drift into the measurement path.
For applications such as semiconductor test, automated test equipment, precision data acquisition and low-level signal switching, a relay should not simply fit the available space. It should also help preserve the integrity of the signal being measured.
