Reed Relays remain an attractive solution for switching applications. Having a metallic path, they do not suffer from the relatively high and non-linear contact resistance together with the high off-state leakage current usually associated with solid state relays.
High voltage reed relays are intended for applications where the voltages are beyond the capabilities of conventional reed relays. They use vacuum reed switches to maximise the voltage rating for a given blade separation and to manage arc duration as the contacts open or close.
Any loss of seal will rapidly degrade the switch operation so reed switches have to be carefully managed as they are packaged into reed relays, using suitable encapsulation materials and Pickering’s SoftCenter® technology. The relay design must ensure there is adequate clearance distance both internally and externally for the rated voltages, something which also needs to be considered for the PCB layout.
The Industry's Smallest High Voltage SIL Reed Relays
Pickering’s new Series 119 range, for up to 3kV stand-off and 1kV switching, is the industry’s smallest high voltage Single-In-Line Reed Relay now available. They are intended for voltages very much higher than standard small SIL relays, ideal for Cable and Backplane Testers, Mixed Signal ATE or other applications where High Voltage switching is required.
The vacuumed sputtered ruthenium reed switches have a superb low level performance also, which makes them an ideal choice where a wide range of signals are involved.
Four versions are available, all with either 3, 5 or 12 volt operating coils. The 1 Form A, 1kV version has a package and pin configuration compatible with Pickering’s standard 109P reed relay, i.e. 4 pins on 0.15 inches (3.8mm) pitch. These can be stacked side-by-side for maximum packing density (all Pickering Reed Relays have full magnetic screening allowing side by side operation). The other types have package lengths and pin configurations appropriate for their voltage ratings.
The range is based on the long established Series 109P style of plastic package with an internal mu-metal magnetic screen which allows maximum packing density and are made using Pickering’s SoftCenter® construction.
If you are interested in the Pickering Series 119 you can request Free samples here:
Instead of the more usual hard moulded package, Pickering use our SoftCenter® technology, whereby a soft inner material is used to protect the delicate glass to metal seal of the reed switch capsule against expansion mismatches. This de-stresses the switch ensuring accurate alignment of the switch blades which in turn gives a longer and more reliable life.
Even quite minor stresses, tensile, compressive or torsional can slightly move the contact area of the switch blades which results in contact resistance instability which can easily be detected during extended life testing.
Pickering also offer other high voltage dry Reed Relays, the Series 104 for up to 3kV stand-off, 25 Watts switching and the Series 60, 62, 63 and 65 for up to 15kV stand-off. The Series 62 and 63 also come with push on connections on the top face. These feature tungsten plated contacts to ensure a long and reliable life.
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