Switch Types
The three most common coaxial rf switch types are (1) single-pole-double-throw (SPDT), (2) Transfer (DPDT), and (3) multiposition.
SPDT Switch: A single-pole, double-throw switch has one input port and two selectable output ports. RF ONE now offers SPDT switches with SMA, 2.92mm, 2.4mm, 1.85mm connectors from DC to 67GHz.
SPDT Terminated Switch: A single-pole,double-throw switch with one open output RF port internally terminated in a 50-ohm resistive load.
Multi-Position Switch: A switch with one input and more than two outputs.
Multi-Position Terminated Switch: A multi-position switch with each unused or open output RF port internally terminated in a 50-Ohm resistive load.
Transfer Switch (DPDT): A transfer switch has two independent paths that operate simultaneously in either of two selected positions. These pairs are actuated simultaneously. This actuation is similar to that of a double-pole double-throw switch.
Actuator
An actuator is the electromechanical mechanism that transfers the RF contacts from one position to another upon DC command.
Failsafe: A failsafe switch reverts to the default or failsafe position when the actuating voltage is removed. This is realized by a return spring within the drive mechanism. This type of switch requires the continuous application of operating voltage to select and hold any position.
Latching: A latching switch remains in the selected position whether or not voltage is maintained. This can be accomplished with either a magnetic or mechanical latching mechanism.
Momentary (Normally Open): A mode of operation in which all output ports of the switch are disconnected from the input port until a voltage is applied to maintain a selected position. The switch returns to its open position with the removal of voltage.
Actuator Voltage: All RF ONE standard electromechanical switches are available with 12 Vdc, 18 Vdc, 24 Vdc, and 28 Vdc. Other voltages can be supplied depending on the request.
Electromechanical Switch Options
TTL Logic: Transistor-transistor-logic driver circuitry enables the status of the switch to be controlled by the level of the TTL Logic input. Users can apply the power voltage across a pair of designated power terminals and then control the RF Switches operation with a 5 volt control circuitry.
RF ONE’s TTL Logic has a remarkable circuitry which will enable your system to run cooler and will save a substantial power supply to the switches.
Indicator: Indicators tell the system which position the switch is in. Indicators are usually a set of internally mounted contacts mechanically connected to the switch actuator allowing external monitoring of switch RF status.
Power Interface: All RF ONE standard electromechanical switches are available with solder pins and D-Sub connectors. We can also supply other sources of power interface such as the Micro D’Sub and various pin configurations.
Self Cutoff: This applies to latching switches only. A switch that has the ability to disconnect the actuator drive circuit so that D.C. current will not be consumed after switching has been accomplished.
For further details, please contact sales@rfone.cn.
