Understanding High Power SwitchingWhere to use our high power PIN devises: PIN switches may be applied to any control situation found in today's systems. T/R switches, antenna selectors, polarity switches, switch filters, switched attenuators, duplexers and receiver protectors have been successfully configured with Mercury's high power control designs.
What can high power PIN switches do: Mercury PIN switches are available in single or multi-throw layouts; ported in both waveguide and coax with reciprocal power. They are usually reflective, which means that power presented at any OFF port will be reflected. This is important to bear in mind when deciding where to locate isolators or circulators in the system to protect system elements sensitive to excessive reflected power.
High power PIN switches are often designed to be cold-switched when there is no significant RF power in the system. Mercury also designs hot-switched products; just let us know the details of your pulse characteristics and layout of the system elements nearby the switch.
Generally low loss devices, our PIN switches usually require only modest heat sinking; although thermal path management should be discussed under special circumstances.
Dependent on the peak power (RF voltage) levels encountered, Mercury switches will switch from one position to another in the range of 50 nanoseconds to a few microseconds; faster than electromechanical switches which take from 20 to 100 milliseconds to switch. High power PIN switches are also three to five times faster than ferrite switches.
Typically they offer higher isolation; 40 to 50 dB for most standard high power PIN switches, versus ferrite switches get only the 20 to 25 dB isolation of their hybrid or circulator structure while typical isolation of an electromechanical switch is about 70 dB.
PIN switches may be easily designed to equal the inherent high isolation of electromechanical switches, but there are trade-offs on insertion loss, cost and size.
Properly specified and applied, a PIN switch should last the life of the system. The PIN device is all solid state, so there is virtually nothing to wear out. Electromechanical switches have a practical lifetime ranging from 250,000 cycles to 2,000,000 cycles, after which they must be replaced. Consider the cost of system repair over the expected life of the system when choosing mechanical vs PIN switches, and you will usually find that the PIN switch is easily cost justified.
Reliability Process Controls: Mercury has created and implemented a set of controls and processes that assure the integrity of every unit shipped. We perform high power testing as an in-process test during the production cycle. This allows us to recognize and rectify component issues before the switch is capped, while corrective action can still be taken to save the switch and your schedule. End item high power testing is also accomplished on every design. In short, our process controls assure you of the integrity of every item shipped.